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Comets top Hanover; Bri Jarvis nets hat trick! – St. Albans Messenger

The BFA-St. Albans Comets won 4-1 over Hanover on Wednesday, Dec. 27, thanks in part to a hat trick by senior forward Bri Jarvis.

Jarvis put the Comets on the board at 12:48 in the first period on an assist from Kali Cushing. Jarvis netted her second goal at 13:58 in the second period, assisted by Rae Alexander. Alexander scored the Comets' third goal at 3:42 in the third, assisted by Jarvis. Jarvis completed her hat trick at 14:30 in the third with an unassisted goal.

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Comets top Hanover; Bri Jarvis nets hat trick! - St. Albans Messenger

Despite a Returning Nico Daws in Net, Comets Drop Their Third-Straight in a 3-2 Loss to Cleveland – WKTV

UTICA, N.Y. -- It was a much-anticipated return for goalie Nico Daws in net for Utica at home against AHL North-leading Cleveland, but the Monsters edge out the Comets for a 3-2 victory.

Utica scored the first goal in the first period off the stick of Graeme Clarke on the right side. It was Clarke's tenth goal of the season.

Cleveland would rally to earn the next two goals in the period. The first came from Roman Ahcan, less than two minutes into the frame. The next was scored by Jake Gaudet at the 10:09 mark.

Things got chippy late in the frame, as twice in less than a minute, Monsters players skated into goalie Nico Daws and knocking him to the ice. The second time, Carson Meyer's offense appeared more blatant to many.

A large-scale brawl ensued, eventually translating into a power play opportunity for the Comets. Within eight seconds on the advantage, Kyle Criscuolo rebounded and scored on a Xavier Parent shot that was stopped, knotting things up at two goals apiece in the second period.

The Comets drop their third-straight in a tense and very physical loss to Cleveland

In the third period, Cleveland's Carson Meyer added to the disdain of the Utica faithful when he collected what would turn out to be the game-winning goal, giving the Monsters the 3-2 lead.

Utica drops its third-straight game. They resume play on Wednesday evening on the road at Lehigh Valley. Puck drop is set for 7:05 p.m.

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Despite a Returning Nico Daws in Net, Comets Drop Their Third-Straight in a 3-2 Loss to Cleveland - WKTV

When to Watch the Eta Aquariids Meteor Shower Peak – The New York Times

On any given night, far from bright city lights, theres a chance that youll see a beautiful streak shoot across the sky as a meteor flies overhead. But on special dates scattered throughout the year, skywatchers can catch a multitude of flares as meteor showers burst in the darkness.

Meteor showers occur when our planet runs into the debris fields left behind by icy comets or rocky asteroids going around the sun. These small particles burn up in the atmosphere, leading to blazing trails of light. The regularity of orbital mechanics means that any given meteor shower happens at roughly the same time each year, with the changing phases of the bright moon being the main variable affecting their visibility.

The next event is the Eta Aquariids, one of two showers resulting from the debris field of Halleys comet (the other is the Orionids in October). Debris will enter over Earths Equator, meaning it will be visible in both hemispheres all over the world. In past years, the Eta Aquariids have produced 45 to 85 meteors per hour in dark sky conditions.

Unfortunately, the peak for this shower coincides with a full moon on Friday, May 5, into Saturday, May 6, limiting visibility. But the shower should be highly active for roughly a week before and after that date.

Subscribe to the Times Space and Astronomy Calendar to get a reminder ahead of this and other events.

The best practice is to head out to the countryside and get as far from artificial light sources as possible. People in rural areas may have the luxury of just stepping outside. But city-dwellers have options, too.

Many cities have an astronomical society that maintains a dedicated dark sky area. I would suggest contacting them and finding out where they have their location, Robert Lunsford, the secretary general of the International Meteor Organization, said in an interview with The New York Times in 2022.

Meteor showers are usually best viewed when the sky is darkest, after midnight but before sunrise. To see as many meteors as possible, wait 30 to 45 minutes after you get to your viewing location. That will allow your eyes to adjust to the dark. Then lie back and take in a large swath of the night sky. Clear nights, higher altitudes and times when the moon is slim or absent are best. Mr. Lunsford suggested a good rule of thumb: The more stars you can see, the more meteors you can see.

Binoculars or telescopes arent necessary for meteor showers, and in fact will limit your view.

Each shower peaks on a certain date when Earth is plowing into the densest portion of the debris field, though in some cases many meteors can still be seen before or after that specific night.

A shower is named for a constellation in the part of the sky it appears to streak from. But theres no need to be perfectly versed in every detail of the celestial sphere. Meteors should be visible all over the sky during any given shower.

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When to Watch the Eta Aquariids Meteor Shower Peak - The New York Times

Eta Aquarid meteor shower 2023 peaking now! See pieces of Halley’s Comet in the night sky – Space.com

The annual Eta Aquarids meteor shower peaks on Friday (May 5) and Saturday (May 6), offering skywatchers the opportunity to see debris from Halley's Comet as it enters Earth's atmosphere at incredible speeds and burns up.

This year the meteor shower began lighting up the night sky over Earth on April 19 and will last until May 28, so even after its peak there will be plenty of opportunity to catch fireballs streaking through the sky.

At its peak, the Eta Aquarid meteor shower has a rate of around 55 meteorites per hour, but this rate is calculated assuming perfect viewing conditions such as completely dark skies and ideal weather. This means skywatchers should realistically expect to see fewer Eta Aquarids meteors than this.

According to In the Sky (opens in new tab), from New York City the Eta Aquarid meteor shower becomes visible each morning at around 2:32 a.m. EDT (0632 GMT) with it remaining active until around the break of dawn at 5:16 a.m. EDT (0916 GMT).

Related: Meteor showers 2023: Where, when and how to see them

Spotting the Eta Aquarids is even tougher in the Northern Hemisphere because the meteor shower's radiant, the point at which its meteors appear to stream, is located in the Aquarius constellation near one of the constellation's brightest stars, beta Aquarii, which only reaches a low altitude above the eastern horizon.

In the Northern Hemisphere, the Eta Aquarids' radiant is at its highest just before sunrise with it appearing over the horizon to the east for just a few hours. This makes the early dawn the best time to spot the most meteors. The reason why more meteors are visible when the radiant rises to its highest point, or "culminates," is because this is the time at which this region of Earth is turned towards the direction of incoming meteors.

This results in more meteors raining down vertically and creating short trails close to the star beta Aquarii. At other times, though meteors will be fewer, the fact they take more horizontal paths through Earth's atmosphere means they take longer to burn up, and as a result, these long-lived meteors create relatively stretched trails over Earth.

Skywatchers who can't make it outdoors to view the meteor shower during its peak have the option to watch it streamed online live and for free. The Asahi Shimbun Space Department and the National Astronomical Observatory of Japan (NAOJ) began a livestream (opens in new tab) of the Eta Aquariids from the Subaru Telescope, MaunaKea Hawaii, on April 18.

Like all meteor showers, the Eta Aquarids are created when Earth during its 365.25-day orbit of the sun passes through a cloud of dust and debris left by a comet or an asteroid. And the Eta Aquarids have a very famous progenitor indeed, arguably the most well-known comet, Halley's Comet, or more formally 1P/Halley.

As comets come close to the sun, the radiation from our star causes the material that composes them to heat up. This results in solid ice within the cometary body transforming directly into gas, a process called sublimation. As this gas is ejected, it blasts away particles of dust and ice from the comet. This causes these icy bodies to brighten as they approach the sun and also gives them the characteristic glowing aura, or coma, that surrounds them and their cometary tail.

In addition to this, some fragments of this ejected material linger around the sun as the comet orbits, and as the Earth makes its own journey around its parent star, it passes through these clouds usually at the same time each year.

Our planet encounters debris from Halley's Comet every April to May, giving rise to the Eta Aquarids. These dust fragments separated from Halley's Comet hundreds of years ago, something scientists know because the current path of the comet doesn't seem to bring it close enough to the Earth to leave cometary debris that would create meteor showers.

The fragments enter Earth's atmosphere at speeds as great as 148,000 miles per hour, which is 100 times faster than a jet fighter, and burn up at altitudes of around 44 to 62 miles (70 to 100 kilometers) over the surface of the planet.

The last time Halley's Comet's 76-year orbit of the sun brought it past Earth was in 1986 and it won't be back until 2061, according to NASA (opens in new tab). That means for the next 38 years, the closest skywatchers will get to observing the comet is sighting the debris it shed hundreds of years ago as it is destroyed in the atmosphere.

If you want to get a closer look at Aquarius to hopefully see some of the Eta Aquarids, our guides to thebest telescopesandbest binocularsare a great place to start.

And you're looking to snap photos of the night sky in general, check out our guide on how to photograph the moon, as well as our best cameras for astrophotography and best lenses for astrophotography.

Editor's Note: If you catch a photograph of the Eta Aquarid meteor shower and would like to share it with Space.com's readers, send your photo(s), comments, and your name and location to spacephotos@space.com.

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Eta Aquarid meteor shower 2023 peaking now! See pieces of Halley's Comet in the night sky - Space.com

Eta Aquariids meteor shower: When and where you can see it in the UK – Sky News

By Faiza Saqib, News reporter @Faiza__Saqib

Friday 5 May 2023 10:34, UK

The Eta Aquariid meteor shower is expected to peak in the early hours of Saturday 6 May.

It's time to camp out, gather your sleeping bags and prepare for a night of stargazing, as you might be able to see a spectacular display of 120-160 shooting stars per hour.

The Eta Aquariids occur when the Earth passes through the debris trail of Comet Halley.

Here's everything you need to know.

When is the Eta Aquariids meteor shower this year?

According to Royal Museums Greenwich, the meteor shower is active between 19 April and 28 May but will peak between midnight and dawn on 6 May this year.

Bill Cooke, lead of NASA's Meteoroid Environments Office at the agency's Marshall Space Flight Center in Huntsville, Alabama, said: "A meteor shower is like a normal rain shower, with 50-60 meteors per hour.

"An outburst is like a thunderstorm, with greater than normal meteor activity expected. A meteor storm is like a tornado, where meteor rates are over one thousand per hour."

Where does Eta Aquariids get its name from?

The Eta Aquariids usually peak during early May each year and are known for their speed.

Eta Aquariid gets its name from the constellation in the night sky that it appears to radiate from - the Aquarius constellation.

But instead of being called the Aquarid meteor shower, the name comes from one of the stars from this constellation, Eta Aquarii.

The Eta Aquariid is one of two meteor showers created by debris from Comet Halley.

Halleys Comet is visible from Earth once every 76 years or so.

"The pieces of space debris that interact with our atmosphere to create the Eta Aquarids originate from comet 1P/Halley," the NASA website has said.

Comet Halley was first discovered by English Astronomer Edmund Halley in 1705.

He predicted the orbit of the comet through past observations of comets, suggesting that these sightings were, in fact, all the same comet.

Halley is known to be the most famous comet and was last seen in 1986.

Nasa said it will return in 2061 on its regular 76-year journey around the Sun.

How can I see it in the UK?

The Eta Aquariid meteor shower can be viewed in the Northern and Southern Hemispheres, but NASA has said that the highest visibility will be in the Southern Hemisphere.

"This is due to the radiant's location in the constellation of Aquarius. Meteors will be observable after midnight, but the peak times are 3-4 am until dawn," NASA said.

The Royal Museums Greenwich website says: "This shower favours the Southern Hemisphere and will appear low in the sky for northerly latitudes (such as the UK) in the early predawn hours."

In order to get the best view, here's what you can do:

Be sure to check the weather forecast! If it is cloudy, try a day before or after the peak viewing period.

The Met Office has said Friday will be a day of sunshine and showers.

Saturday will be another cloudy and wet day for many across the UK.

So be sure to prepare in advance if you want to catch the Eta Aquariid meteor shower.

NASA has also advised people to:

Get as far away from city lights as possible to get the best view of the meteor shower.

Give yourself 30 minutes in the dark for your eyes to adapt.

Do not look at your phone - again, stay away from the light.

Try not to look at the moon.

And last but not least, get comfy! For the best stargazing method, lie down and watch the night sky.

Read more from Sky News:World's first artificial shooting star displayElon Musk 'wrong' to call for pause in development of AI

What is a meteor shower?

Simply put, a meteor shower is a space rock or meteoroid entering Earth's atmosphere.

"As the space rock falls toward Earth, the resistance-or drag-of the air on the rock makes it extremely hot. What we see is a 'shooting star.'

"That bright streak is not actually the rock, but rather the glowing hot air as the hot rock zips through the atmosphere," NASA has said.

"When Earth encounters many meteoroids at once, we call it a meteor shower," it adds.

Here are some meteor showers over the years

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Eta Aquariids meteor shower: When and where you can see it in the UK - Sky News

Athlete of the Week: Amelia Weber’s grand slam helped boost … – St. Albans Messenger

Amelia Weber had a dominant week at the plate, going 7 for 9, with six RBI, one double, one triple, and a grand slam while playing flawless defense in the outfield. The grand slam helped lift the Comets comfortably past visiting Missisquoi Valley Union on April 25.

Q&A with Amelia Weber

What will you remember most about hitting the home run to open up the game against MVU? The part I will remember most and the best part of the whole thing was coming down the third base line and seeing my team waiting for me to touch home plate and then being in that huge huddle with them.

What three things do you love about this team that you feel contribute to its success? Three things I love about this team that contributes to our success is the way we treat each other like family, how we give back to the community, and how hard we all work during practices.

What are you most looking forward to in the second half of the season? Im looking forward to our competitive games and all the milestones that will lead us to success. I also want to thank all of the coaches for their commitment to the team and helping us to become better softball players everyday.

Comet coach Bert Berthiaume: Amelia was brought up to varsity this year as a sophomore to be in a reserve role as she worked on her game, and quickly emerged as someone ready to contribute immediately. Her grand slam against MVU was huge in giving the Comets a lead that would carry them to the victory. On April 29, in a close game early against Colchester she had a base loaded hit that drove in two. Shes a hard working athlete whos often found in the weight room when shes not on the softball field. Shes extremely coachable and has quickly earned the respect from the coaching staff as well as her peers. Shes remained humble in her early season success, and she has made all of us very proud.

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Athlete of the Week: Amelia Weber's grand slam helped boost ... - St. Albans Messenger

Harlow homers, drives in five runs in Comets’ win over Bassett – YourGV.com

BASSETT Five games. Four days. No problem.

The Halifax County softball team wrapped a hectic week with an 11-3 win over Bassett in Piedmont District action Wednesday evening.

Playing its fifth game since Monday, Halifax (15-3, 7-0 Piedmont) showed little rust against the Bengals, especially in the third and fourth innings where the Comets broke open a close game with a combined seven runs.

Senior Jadyn Harlow played a big role in the rally, smacking her third home run in two days, a two-run shot to center field in the top of the fourth, on her way to a game-high five RBIs. Harlow homered twice in Halifaxs game against Bassett Wednesday night.

Ive really just been looking for base hits, not looking to hit a home run but theyre nice, Harlow said. But its been motivating to have my teammates behind me. When youre running around the bases and theyre at home yelling, bring it home, bring it home, its really a motivational tool. Its a good feeling and makes you want to keep going.

The Comets have now won six in a row with five of those wins coming this week. This week, Halifax has defeated its opponents by a combined average of 11.8 runs per game while averaging 14 runs per game and giving up 3.7 per game.

Its really been the whole team, Harlow said of the Comets mental tenacity this week. Some of us have gotten tired, weve felt like weve had enough for the week, we needed a break, and we would come behind each other like, hey, we got one more down, we can do it, just a few more, then we can get a break for the weekend. And I think all of us pushing each other have helped us get through this week.

It took the whole team to get through this week, our big players have stepped up and helped us get through this week, said junior Emma Payne.

Harlow led Halifax with game-highs of three hits and five RBIs while senior Kamyria Woody-Giggetts smacked two hits and recorded two steals. Woody-Giggetts, senior Shamya Hankins, junior Abby Duffer, sophomore Avarie Bowen and junior Emma Shepperd drove in a run apiece.

Payne picked up the win in the circle, giving up two hits and three runs none earned while striking out eight in seven innings pitched.

Its great, I was just working on trying to stay consistent and throw strikes, Payne said. But a long week, our other pitchers really had to step up and it took the entire pitching staff to get through the week and they really stepped up. Five wins is great.

Payne expressed her pride in the Comets entire pitching staff.

I couldnt be more proud, she said. I know they were a little nervous coming in because they didnt know what to expect and they came out and did it. They were throwing pitches, hitting their spots, I was really impressed.

Halifax got out to the early lead, scoring a run in the top of the first inning. Payne worked a one-out walk to get things going and Hankins followed with a single to left field to put runners on first and second. Harlow didnt stand on ceremony, bringing Payne home with her single to right to make it 1-0.

Bassett (10-7, 5-5) struck back in its half, scoring two runs to take the lead. Senior Trinity Gilbert worked a one-out walk and stole second base to start the rally and junior Zoie Pace reached on an error on her flyball to put runners on the corners. Junior Breanna Cooper knotted the score at 1-1 with her RBI ground out to first and senior Camryn Martin put the Bengals in front with her RBI single to center.

The Bengals pushed their lead to 3-1 when senior Gracie Ratcliff scored on an error on sophomore Shaniyah Menefees bunt.

It would be the last time Bassett led as the Comets struck for three runs in the third to take the lead for good. Woody-Giggetts kicked the rally off with a lead-off walk and proceeded to steal second base to get into scoring position. She advanced to third on a wild pitch and came home to score on an error on Hankins groundball to short to pull Halifax within one. Harlow knotted the score with her double to right that plated Payne and Duffer scored Hankins with the go-ahead run on her ground out to first.

The fourth inning proved to be the difference, though, as the Comets scored four runs in the frame to create space. Freshman Hannah Abbott scored on an error on Bowens bunt single and Harlow capped the rally with her three-run blast to center that made it 8-3.

Halifax kept things rolling with a pair of runs in the fifth on Bowens RBI ground and Woody-Giggetts run-scoring single that pushed the Comets lead to 10-3 moving into the back three.

Shepperd rounded out the scoring in the seventh on her RBI groundout to short.

Halifax returns to action Monday when it hosts Nottaway in a doubleheader starting at 4:30 p.m.

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Harlow homers, drives in five runs in Comets' win over Bassett - YourGV.com

Wellington vs. Amherst baseball: Comets come out ahead in 1-0 pitchers duel – The Morning Journal

A classic pitchers duel took place between Wellington and Amherst on May 5 in a nonconference matchup, as the two teams were scoreless through 5 1/2 innings in Amherst.

The pace was crisp and both starters, Cam Gendics for the Comets and Johnnie Kinter for the Dukes, pitched marvelously. Though one team had to fall, as Gendics and the Comets came out with a 1-0 victory, with Anthony Heikkinen earning a two-out save.

The game was played out in a playoff atmosphere, as the postseason is less than two weeks away and Amherst neck-and-neck with North Ridgeville for the SWC crown.

I thought both pitchers were fantastic, Amherst coach Matt Rositano said. (Johnnie) Kinter is really good, thats one of the better pitchers weve faced this year. Cam was on his game the entire time he was out there. We had him on a pitch count so he could be available next week. I know he wanted to stay out there. But weve got more important games on Monday and Wednesday.

Everything went smoothly until Amherst put Chase Mayer, fresh off a 15-strikeout no-hitter of Elyria May 4, in to pinch hit for Devin Pritt to lead off the bottom of the sixth. Mayer laid down a bunt, and the throw sailed wide of the mark at first base and he raced around to third. One out and three batters later, Cam Gendics helped his own cause with an opposite-field blooper to right that scored Mayer.

Definitely not one of our best games, but Coach Roz always says put the ball in play and good things will happen, Mayer said. I got a bunt down and an overthrow to first, and I ended up getting to third. Cam Gendics came up with a hit and I ended up scoring. That was the difference in the game.

Being on a pitch count and getting Mayer over to third to swing momentum in their favor, Gendics capitalized when it came time for him to hit with two on and one down in that playoff atmosphere with runs at a premium.

That was a big moment, Gendics said. He came in and did his job, and we capitalized on the error. Especially with our pitching staff, that one run is going to be really big.

Wellington coach Dan Davison was pleased with the overall effort, as it was a great game outside of the one miscue.

It was a really good game, Davison said. Obviously, they have a lot more weapons than we do, but we come in here with the belief that we can win the game and we belong on the field with these guys. Johnnie pitched a great game and the defense was solid up until that one bunt. Just didnt have the grip on the baseball when he made the throw, I could see it when he threw it.

Wellington had a chance to knot the game up, with two runners on base before Heikkinen struck out the last batter to lock down the save.

While that moment obviously stings, Davison still had an optimistic outlook on the game itself, as both teams got a good test ahead of tournament time.

All in all, Im not too displeased. We hit the ball OK and gave ourselves a chance again at the end of the game to tie it up and go somewhere with it, and it just didnt happen tonight.

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Wellington vs. Amherst baseball: Comets come out ahead in 1-0 pitchers duel - The Morning Journal

Patience pays off in Lady Bombers win over Lady Comets – Paducah Sun

The Carlisle County Lady Comets hosted the Ballard Memorial Lady Bombers on Thursday night. With the score knotted 3-3 for most of the game, the Lady Bombers were patient at the plate, scoring big runs down the stretch to secure the 5-3 win.

That 3-3 score seemed stuck as the Lady Comets tied things up in the bottom of the third inning and the score wouldnt change until the Lady Bombers runs in the top of the seventh.

When youve got two great teams like these, a senior loaded team in Carlisle and a young team with us patience is key, Ballard Memorial head coach Scott Alexander said. To come up, even when its a one-run ballgame like that, a simple sac fly can make the difference in the game.

That sacrifice fly came courtesy of Aubrey Alexander with the bases loaded and one out. Her strategically placed ball gave Serenity Owens room to score the leading run and an error on the throw game Adalyn Hargrove the time she needed to score the final run.

Thats the way weve been so far, Alexander said. We get behind and we always fight back late. It says a lot about the grit we have as a team, its great to see.

Madyson Bohde claimed the win for Ballard Memorial in the circle, allowing two hits, three runs and striking out eight on a 127-82 pitch-strike count. She also contributed to the first run of the evening when she connected on a single to score Trinity Williams who knocked a double in the previous at-bat.

Carlisle County would answer back in their portion of the first inning. Junior Laney Shehorn got things going with a fly ball double to left field and after two quick strikeouts, Anna Russelburg brought home Shehorn on a line drive and reached on an error. They doubled down in the following at-bat when Lilyan Shehorn knocked out a line drive single to score Russelburg and take the 2-1 lead.

The Lady Bombers would get back on top in the top of the second. A single from Kinley Doublin and double from Johnna Riggs put runners on bases and put Owens in prime position to bring home her teammates on a ground ball turned error.

This put Ballard up 3-2 heading into the third inning.

The tying run in the bottom of the third on a fly out from Karlie Gibson to score Laney Shehorn who was hit by a pitch to start the inning.

Strikeouts and fly outs and ground outs were aplenty for the following few innings as defenses prevailed and the 3-3 score froze.

For the Lady Comets it was Rhianna Thomason who controlled the circle and contributed to said strikeouts. She allowed nine hits, five runs, walked two and struck out five on a 101-75 pitch-strike count.

Despite the loss, the Carlisle County Lady Comets celebrated their eight seniors after the game on senior night. Alyssa Aikins, Tori Burgess, Rorey Eddleman, Chyenne Geveden, Karlie Gibson, Alexis Jones, Lilyan Shehorn and Rhianna Thomason loaded the Lady Comets senior stacked team.

BLLR 1 2 0 0 0 0 0 5-9-3

CRLS 2 0 1 0 0 0 0 3-2-3

2B: BM T. Williams, K. OConnor, J. Riggs; CC L. Shehorn

TB: BM T. Williams 3, K. OConnor 3, M. Bohde 2, J. Riggs 2, K. Doublin 1, A. Alexander 1; CC L. Shehorn 2, L. Shehorn 1

RECORDS: Ballard Memorial (18-4); Carlisle County (12-11)

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Patience pays off in Lady Bombers win over Lady Comets - Paducah Sun

Mackinaw City baseball fights back to earn split with Ellsworth – Cheboygan Daily Tribune

MACKINAW CITY The Northern Lakes Conference baseball title looks like it's up for grabs this spring.

For head coach Elijah May and the Mackinaw City Comets, they believe theyre right in the mix.

And even after a 5-0 defeat to Ellsworth in game one of a crucial NLC doubleheader on Thursday, the Comets bounced back and kept themselves alive for a championship they crave.

Sparked by the pitching of senior Lars Huffman, the Cometsavenged the early setback by capturing a hard-fought 1-0 victory in game two and earning a split at home.

Were happy with a split tonight. That keeps us alive and in the drivers seat for the league, said May. Well see what Ellsworth and Harbor Light do with each other. Wed love to come away with at least a share of the league. Ellsworths tough."

The only run of game two came in the first inning, when Huffman avoided being caught in a rundown and made it into home plate safely, giving Mackinaw City a 1-0 lead. On the mound, Huffman delivered a strong performance, tossing five shutout innings with six strikeouts, three hits allowed and one walk. Huffmans pitching record is now 7-0 this season.

Huffman finished with a hit and two stolen bases for the Comets (13-4, 3-1 NLC), who received a hit and a stolen base apiece from Trystan Swanson and Lucas Bergstrom. Myran Thompson stole two bases.

The one bad inning for the Comets came in the first of game one, when they allowed five runs to the Lancers.

Despite taking the loss on the mound, junior pitcher Sabastian Pierce was solid, striking out five, allowing four hits and walking three in five innings of work.

Huffman finished 2-for-3 with two stolen bases to lead the Mackinaw City offense, while Tyler Hingston stole a base.

Ellsworth swept their way through our league on their way to a first-place finish last year, and one of our goals coming into this season was to beat them at our place this year, May said. Our guys stepped up defensively tonight and made a ton of plays. Both Sabastian Pierce and Lars Huffman pitched well tonight. Even in the loss in game one after a tough first inning, Sabastian Pierce was able to settle in and pitch fourstraight scoreless innings.

Tonight was great baseball all around. Both teams played clean baseball and were solid defensively."

On Wednesday, the Comets captured a 12-5 victory over Alanson in a non-conference game.

Eighth grader Jacob Sroka was the winning pitcher, striking out four and allowing no hits in three innings of work. Throwing an inning apiece were Swanson, Hingston and Nick Vieau, who tallied two strikeouts each. Thompson struck out a batter in 1/3 innings pitched and Braylon Currie added a strikeout in 2/3 innings pitched.

Vieau led the Comets at the plate by going 3-for-4 with a run scored, whileHuffman, who hit an inside-the-park home run, was 2-for-3 with three RBI and three runs scored. Adding two hits apiece were Currie (four RBI), Thompson (triple, RBI) and Connor Robertson (RBI, run). Bergstrom added a hit and scored twice. Swanson scored two runs.

Bad innings hurt softball Comets in losses to Ellsworth

MACKINAW CITY All it takes is a bad inning or two to hurt your chances.

Unfortunately for the Mackinaw City softball team, it had a rough inning in each of its contests against the Ellsworth Lancers, who captured a sweep by earning 12-5 and 9-4 victories in a Northern Lakes doubleheaderon Thursday.

They (Ellsworth) are a good team, said Mackinaw City coach Bianca Thompson. They have some really good pitchers. Our batters werent coming (up with big hits) tonight. We had a few difficulties there. We have a younger team, and unfortunately, part of it showed tonight. Half of our lineup is seventh or eighth grade. Going up against some of those older girls is sometimes hard.

In the opener, the Comets (10-3, 2-2 NLC) were led by two singles and a stolen base from Madison Smith, while Julia Sullivan singled and stole three bases. Poppy Wallace scored a run and stole a base. Marlie Postula scored a run.

Postula took the loss on the mound, striking out seven, allowing 12 hits and walking two in six innings pitched.

After falling behind 5-0 early, the Comets fought back to cut the Ellsworth lead to 6-3 in game two. However, the Lancers responded with three runs and pulled away for the win.

Postula doubled, singled, had two RBI and stole a base to lead Mackinaw City, while Vanessa Groenewoud tallied two singles, Kenzlie Currie doubled, scored two runs and stole a base, Rian Esper singled and added three stolen bases, Wallace scored a run and stole a base, and Smith stole a base.

Postula was the losing pitcher, striking out 11, allowing eight hits and walking three in six innings of work.

I have to give credit where creditis due. (Ellsworth's) pitcher can throw, Thompson said. She has one heck of a changeup. We had a hard time getting around on her.We had one bad inning in both games. If you took that one inning away, the score would have looked a whole lot different. I toldthese ladies we are just going to move on to the next game and keep their chins up and keep having fun. You can't change the last play, we have to look forward to the next one.

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Mackinaw City baseball fights back to earn split with Ellsworth - Cheboygan Daily Tribune

Riverhawks Stifled by Comets | The Daily Chronicle – Centralia Chronicle

By The Chronicle staff

The Toledo baseball teams final tune-up before district play begins went awry Monday, as the Riverhawks fell victim to one of the best pitchers in the area regardless of classification in a 3-0 non-league loss to 1B Naselle.

Kolten Lindstrom shoved for the Comets, giving up just one hit a single to Rayder Stemkoski in the second and striking out nine. Toledo got one baserunner on a dropped third strike and another on an error, but never got anybody past second base.

Opposite Lindstrom, Toledo went with its own ace, but Naselle got to Caiden Schultz for a run in the second and a run in the third, and with low stakes on the table coach Mack Gaul pulled him after 67 pitches for Kaven Winters. The two only allowed three hits, but issued five walks each, giving the defending 1B State champs plenty to work with for free.

Toledo, locked into the No. 2 seed in the Central 2B League, will host a three-team pod Saturday in the District 4 tournament, and face the winner of a loser-out game in the quarterfinals.

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Riverhawks Stifled by Comets | The Daily Chronicle - Centralia Chronicle

Wow. Weird ‘rock comet’ 3200 Phaethon is way stranger than we … – The Weather Network

First, a few years ago, NASA's Parker Solar Probe captured the first image of Phaethon's debris stream. Then it snapped a second, closer view in September 2022, as seen above. Analysis of these images confirmed what scientists had been speculating about for some time that there is so much material in the stream, there's no way the rock comet's tiny tail could account for it all.

Now, new images of the asteroid revealed something even more interesting. 3200 Phaethon's tail doesn't actually contain any dust at all. Instead, it's composed of sodium gas.

This extreme closeup of 3200 Phaethon was captured by one of NASA's STEREO spacecraft in 2010. The rock comet's short tail extends toward the bottom left of the image. Credit: Science@NASA

"Our analysis shows that Phaethon's comet-like activity cannot be explained by any kind of dust," Qicheng Zhang, a Ph.D. student at Caltech, told NASA.

Zhang is the lead author of a new study in the Planetary Science Journal that details these findings. He and his colleagues gathered images of 3200 Phaethon taken by the coronagraph instruments on board SOHO and another NASA spacecraft, the Solar Terrestrial Relations Observatory (STEREO), between 1997 and 2022.

Coronagraphs work by blocking direct sunlight from entering the camera using a small disk. As a result, the instrument can image the fainter activity around the Sun, such as coronal streamers and coronal mass ejections. The instruments also pick up any objects in the view, such as stars, planets, and even comets and asteroids. Additionally, the Large Angle and Spectrometric Coronagraph (LASCO) on the SOHO spacecraft uses two filters for its images: an orange one sensitive to sodium and a blue one that can detect dust.

"When a comet or asteroid gets close to the sun, the intense radiation environment can release a lot of sodium from the object's surface," study co-author Karl Battams, who is the LASCO principal investigator at the U.S. Naval Research Laboratory, said in an NRL press release. "We can use LASCOs filters to look for signatures of sodium or the presence of dust, helping us understand the processes occurring on the surface of the comet or asteroid."

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Wow. Weird 'rock comet' 3200 Phaethon is way stranger than we ... - The Weather Network

Workington Comets set to take to track this weekend – cumbriacrack … – Cumbria Crack

Workington Comets fans will get a chance to see their new team plying their trade at Northside tomorrow.

Its the new promotions press and practice day with the riders introduced to the media and supporters before having spins around the newly laid track.

The track action starts at noon and the fans are welcome to watch from the public viewing areas at the Northside arena.

The revived Comets supporters club will also be in attendance for anyone wishing to join on the day.

The team has been assembled since late December but wont have the opportunity to track together until next Saturday, May 13, when they ride against Edinburgh in the opening National Development League fixture.

Promoters Andrew Bain and Steve Lawson are hoping that the weather wont put a dampener on proceedings when their team practises tomorrow as showers are forecast for the Workington area.

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Workington Comets set to take to track this weekend - cumbriacrack ... - Cumbria Crack

WNBA: Houston Comets lead all-time standings, followed by Seattle Storm – Swish Appeal

Every fan roots for their team to win the championship this year, but the ultimate goal is to be the greatest franchise of all time. At Swish Appeal we decided to rank all the WNBA teams that have ever existed in order of greatness.

For franchises that have moved to between two or three different cities, I counted them as two or three different teams. You may want to see these franchises ranked as one, but I considered them separately because their fan bases are different in some cases very different (Detroit Shock/Dallas Wings and Orlando Miracle/Connecticut Sun).

This is our article on teams 11 through 1 (the teams with championships). Instead of dividing number of championships won by number of years played and basing the standings on success rate at winning the championship, I put the teams with more championships overall higher. However, to break the tie between teams with the same amount of championships, I gave the edge to the team that collected theirs in the least amount of years.

On this list, there was only one instance of two teams with the same amount of championships AND the same amount of years of existence (the Los Angeles Sparks and Phoenix Mercury). To break that tie, I used the same formula used in the first part of our list (No. 23 through No. 12):

I applied this system to every season of the teams existence and then divided by the number of non-championship-winning seasons to get an average success number. I did this for every team, not just the Sparks and Mercury, so you can see how successful each team has been in their non-championship-winning seasons.

Here are teams 11 through 1:

Of the teams with one championship, the Mystics have had the most opportunities to win, so they come in at the bottom of that tier. Even if I had done the tiebreaker by tiebreaker points instead of number of seasons played, the Mystics would have finished last among the teams with one title. Their tiebreaker score of 12.65375 is on the weaker side, but they have been to the Finals one other time in addition to the year they won it all. Two other times they made semifinal exits and theyve made the playoffs a total of 14 times. Mike Thibault becoming the teams head coach in 2013 and Elena Delle Donne coming over in 2017 laid the foundation for the 2019 championship.

Natasha Cloud

Photo by Ned Dishman/NBAE via Getty Images

The Fever didnt take as long as the Mystics to get the monkey of their back, winning it all for the first time in 2012. But it was a big deal when they did because they had been a good team for a long stretch leading up to 2012; they just hadnt achieved that ultimate goal. 2012 was their eighth straight year in the playoffs with a Finals loss coming in 2009 and semifinal exits coming in 2005, 2007 and 2011. Their best player throughout all of it was the legendary Tamika Catchings, who was ranked as the No. 2 player in WNBA history by ESPN in 2021. The Fever returned to the Finals in 2015, but fell to the team they upset in 2012 (the Minnesota Lynx). They havent been to the playoffs since 2016, but hope to turn things around with 2023 No. 1 pick Aliyah Boston.

Tamika Catchings

Photo by Ron Hoskins/NBAE via Getty Images

The Sky have not been as successful historically as the Fever, but heres where winning a championship with fewer opportunities benefited Chicago. The Skys tiebreaker score of 13.97125 is on the weaker side, but theyve only been around since 2006 and have that one championship, won with Candace Parker, Courtney Vandersloot, Kahleah Copper and Allie Quigley in 2021. In Chicagos second season after drafting Elena Delle Donne at No. 2 overall, it went to the Finals. The great Sylvia Fowles was also a superstar on that team, which was swept by the Mercury in the 2014 Finals. The Sky also have two semifinal exits, including last year after a franchise-record .722 winning percentage in the regular season. They have been to the playoffs eight times.

Courtney Vandersloot (left) and Allie Quigley

Photo by Kena Krutsinger/NBAE via Getty Images

Sacramento was once a proud WNBA and NBA city. The Kings of the NBA finished 48-34 this regular season for their best record since 2005 and earned the No. 3 seed in the Western Conference. Unfortunately, a Sacramento renaissance on the womens side isnt possible at the moment because the Monarchs are defunct. But they, unlike the Sacramento men, who were very successful in the early 2000s, once finished the job and actually brought a championship to Californias capital city (in 2005). They returned to the Finals in 2006 and lost a hard-fought series to the Detroit Shock. Since they only existed for 13 seasons (from the beginning of the league in 1997 to 2009), they come in second place among teams with one title. They would be second by tiebreaker points as well, with a strong 19.9291667 success number.

Erin Buescher (left), Kristin Haynie and Yolanda Griffith (bottom)

Photo by Andrew D. Bernstein/NBAE via Getty Images

Were not counting the Utah and San Antonio years of the Aces franchise. So this ranking system is very kind to the Aces, though it would be kinder if I was doing it by championships per year. Just before their first season in Vegas began, the Aces drafted Aja Wilson at No. 1 in the 2018 draft. The rest has been history. Vegas went 14-20 and missed the playoffs in 2018, but has been to at least the semis every year since. They took a game from the eventual champion Mystics in the 2019 semis before appearing in the Finals in Wilsons first MVP season (2020). 2021 saw them lose in devastating fashion to the Mercury in five games in the semis, but they turned around and won it all last year under first-year head coach Becky Hammon, while Wilson won her second MVP award. With a league-high 31.03 success number in non-championship years, Vegas is in seventh place with an exclamation mark. Its also in position to see a lot more success in the coming years.

Aja Wilson

Photo by Maddie Meyer/Getty Images

WNBA GOAT Diana Taurasi has been leading the Mercury for most of their history. She has delivered three championships (2007, 2009 and 2014). The 2014 championship she won with the help of 2013 No. 1 pick Brittney Griner. Taurasi and Griner returned to the Finals in 2021 with both performing phenomenally in the playoffs, but the Mercury fell to the Sky in four games. Phoenix is one of the original eight that is still going and saw some pretty good success right off the bat before drafting Taurasi in 2004. It went 16-12 in the WNBAs inaugural season and lost in the semis. In the second WNBA season (1998), it went 19-11 and made it to the Finals. The Mercury made it to at least the semifinals six years in a row from 2013 to 2018 and their two Finals losses combined with eight semifinal exits gives them a very good 21.143913 success score in non-championship-winning years.

From left to right: Kelly Miller, Diana Taurasi, Cappie Pondexter, Penny Taylor and Tangela Smith

Photo by Barry Gossage/NBAE via Getty Images

The Mercury have been good in their non-championship-winning years, but the Sparks have been just a little bit better. After the Houston Comets four championships in a row to open the WNBAs existence, LA won the next two (in 2001 and 2002). Michael Cooper was the coach and Lisa Leslie was the star player. In 2008, the Sparks would draft another star player in Candace Parker, who got the monkey off her back with a first championship for her and a third for the franchise in 2016. It was a difficult championship to win, with the Lynx, who were at the time winners of three of the previous five titles, taking LA to five games and only losing by one point in the clincher. Like the Mercury, the Sparks have lost two Finals. Both times they were the defending champs. They fell to the Detroit Shock, two games to one, in 2003 and in 2017 faced a rematch against the Lynx, with Minnesota getting revenge in another five-game series. The Sparks have exited at the semifinal stage seven times in their history and have made the playoffs a league-high 20 times (three more times than the Mercury have made it). Thats a 76.9 percent success rate when it comes to making the postseason.

Lisa Leslie

Photo by Andrew D. Bernstein/Getty Images/WNBAE

The Shock moved to Tulsa in 2010 and then became the Dallas Wings in 2016. Tulsa wasnt very successful and the Wings havent been either, but the Detroit years are legendary. Detroit Pistons legend Bill Laimbeer coached the team from 2003 to 2008 (and for three games in 2009), winning the championship in 2003, 2006 and 2008. Great players such as Swin Cash, Cheryl Ford, Deanna Nolan and Katie Smith defined the run. Detroit went to the Finals in 2007 as well and to the semifinals in 2009, but all of its other seasons resulted in either a first-round exit or a missed postseason. So its tiebreaker score isnt as good as that of the Sparks and Mercury. But the fact that they won three championships in just 12 years puts them at No. 4.

Deanna Nolan (center)

Photo by Allen Einstein/NBAE via Getty Images

There have been 26 WNBA seasons. Over the most recent 12, the Lynx have four championships and the next closest team, the Seattle Storm. has two. Minnesota loves odd-numbered years, having won the title in 2011, 2013, 2015 and 2017. It drafted Maya Moore at No. 1 in the 2011 draft and won it all in Moores rookie season. It was the big four of Seimone Augustus, Moore, Lindsay Whalen and Rebekkah Brunson leading the way that year; Augustus won Finals MVP. Moore won Finals MVP when the same big four claimed the crown again in 2013. Then, the big four added Sylvia Fowles to become the big five and won two more championships, with Fowles earning Finals MVP in 2015 and 2017. The Lynx have two Finals losses, but just two semifinal exits. Their success rate in making the playoffs is 52 percent. So their tiebreaker score is lower than that of the Sparks, Mercury and Detroit Shock, but it is higher than the two teams ahead of them on this list.

Seimone Augustus (left) and Maya Moore

Photo by Kevin C. Cox/Getty Images

The Storm were able to win two championships with the Lauren Jackson/Sue Bird duo (2004 and 2010) and two more with the Breanna Stewart/Sue Bird duo (2018 and 2020). Because they have existed one less year than the Lynx, they come in ahead of Minnesota and at No. 2. Just like the Lynx, they have been a class organization, with Bird setting the tone in that regard. Meanwhile, the versatility of both Jackson and Stewart makes them two of the best players in WNBA history. Seattle fans have been spoiled, getting to root for those two superstars. Of course, they dont feel spoiled right now, with Stewart having signed with the New York Liberty this offseason. The Storm have a very good success rate in making the playoffs (75 percent), but outside of their four championship-winning seasons they have never been to the Finals and have only been to the semis once (2022).

Sue Bird

Photo by Julio Aguilar/Getty Images

The Comets have the best success rate at winning the championship (33.3 percent), so they would be first even if I based it on that, ahead of the Shock (25 percent) and Aces (20 percent). After all these years, their four championships in just 12 years of existence still stands as the greatest accomplishment in WNBA history. It was the big three of Cynthia Cooper, Sheryl Swoopes and Tina Thompson leading the way to the four straight championships from 1997 to 2000. Van Chancellor was the legendary coach at the helm for all four titles, as well as the six years after that. Like the Storm, the Comets never lost in the Finals and only went to the semifinals once outside of their championship-winning seasons. So their tiebreaker score is a weak 13.455. But until a team reaches five championships (or four in less than 12 years), they will reign at No. 1 in my all-time standings.

Tina Thompson

Photo by Bill Baptist/NBAE via Getty Images

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WNBA: Houston Comets lead all-time standings, followed by Seattle Storm - Swish Appeal

Overview | Comets NASA Solar System Exploration

Key FactsComets

Comets are frozen leftovers from the formation of the solar system composed of dust, rock, and ices. They range from a few miles to tens of miles wide, but as they orbit closer to the Sun, they heat up and spew gases and dust into a glowing head that can be larger than a planet. This material forms a tail that stretches millions of miles.

Comets are cosmic snowballs of frozen gases, rock, and dust that orbit the Sun. When frozen, they are the size of a small town. When a comet's orbit brings it close to the Sun, it heats up and spews dust and gases into a giant glowing head larger than most planets. The dust and gases form a tail that stretches away from the Sun for millions of miles. There are likely billions of comets orbiting our Sun in the Kuiper Belt and even more distant Oort Cloud.

The current number of known comets is:

Go farther. Explore Comets in Depth

Key Science Targets

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Overview | Comets NASA Solar System Exploration

What Is a Comet? | NASA Space Place NASA Science for Kids

The Short Answer:

Comets are large objects made of dust and ice that orbit the Sun. Best known for their long, streaming tails, these ancient objects are leftovers from the formation of the solar system 4.6 billion years ago.

Comets, such as the comet ISON pictured here, are thought to hold material from the time when the Sun and planets were forming. They are like giant, frozen time capsules in our solar system. Credit: NASA/MSFC/Aaron Kingery

Comets are mostly found way out in the solar system. Some exist in a wide disk beyond the orbit of Neptune called the Kuiper Belt. We call these short-period comets. They take less than 200 years to orbit the Sun.

Other comets live in the Oort Cloud, the sphere-shaped, outer edge of the solar system that is about 50 times farther away from the Sun than the Kuiper Belt. These are called long-period comets because they take much longer to orbit the Sun. The comet with the longest known orbit takes more than 250,000 years to make just one trip around the Sun!

The Kuiper Belt is beyond the orbits of the planets in our solar system. The Oort Cloud is far beyond the Kuiper belt. Credit: NASA/JPL-Caltech

The gravity of a planet or star can pull comets from their homes in the Kuiper Belt or Oort Cloud. This tug can redirect a comet toward the Sun. The paths of these redirected comets look like long, stretched ovals.

As the comet is pulled faster and faster toward the Sun, it swings around behind the Sun, then heads back toward where it came from. Some comets dive right into the Sun, never to be seen again. When the comet is in the inner solar system, either coming or going, that's when we may see it in our skies.

This animation represents the 76-year, elliptical orbit of Halleys comet (the white dot) against the more circular orbits of the planets. Credit: NASA/JPL-Caltech

At the heart of every comet is a solid, frozen core called the nucleus. This ball of dust and ice is usually less than 10 miles (16 kilometers) across about the size of a small town. When comets are out in the Kuiper Belt or Oort Cloud, scientists believe thats pretty much all there is to them just frozen nuclei.

But when a comet gets close to the Sun, it starts heating up. Eventually, the ice begins to turn to gas. This can also cause jets of gas to burst out of the comet, bringing dust with it. The gas and dust create a huge, fuzzy cloud around the nucleus called the coma.

This diagram shows the anatomy of a comet. Credit: NASA/JPL-Caltech

As dust and gases stream away from the nucleus, sunlight and particles coming from the Sun push them into a bright tail that stretches behind the comet for millions of miles.

When astronomers look closely, they find that comets actually have two separate tails. One looks white and is made of dust. This dust tail traces a broad, gently curving path behind the comet. The other tail is bluish and is made up of electrically charged gas molecules, or ions. The ion tail always points directly away from the Sun.

A comet has two tails that get longer the closer it gets to the Sun. Both tails are always directed away from the Sun. The ion tail (blue) always points directly away from the Sun, while the dust tail (yellow) points away from the Sun in a slightly different direction than the ion tail. Credit: NASA/JPL-Caltech

People have been interested in comets for thousands of years. But it wasn't possible to get a good view of a comet nucleus from Earth since it is shrouded by the gas and dust of the coma. In recent years, though, several spacecraft have had the chance to study comets up close.

NASAs Stardust mission collected samples from Comet Wild 2 (prounounced like Vilt two) and brought them back to Earth. Scientists found those particles to be rich in hydrocarbons, which are chemicals we consider the building blocks of life.

Rosetta, a mission of the European Space Agency that had several NASA instruments onboard, studied Comet 67P Churyumov-Gerasimenko. Rosetta dropped a lander on the nucleus, then orbited the comet for two years. Rosetta detected building blocks of life on this comet, too. And images showed Comet 67P to be a rugged object with lots of activity shaping its surface.

Rosetta captured incredible images of the rubber ducky-shaped Comet 67P. Credit: ESA/Rosetta/NavCam CC BY-SA IGO 3.0

Thanks to these missions and others like them, we now know a lot more about the structure of comets and the types of chemicals found on and around them. Weve even learned a bit more about the formation of our solar system!

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What Is a Comet? | NASA Space Place NASA Science for Kids

Comet – Wikipedia

Natural object in space that releases gas

A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process that is called outgassing. This produces a visible atmosphere or coma, and sometimes also a tail. These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comet nuclei range from a few hundred meters to tens of kilometers across and are composed of loose collections of ice, dust, and small rocky particles. The coma may be up to 15 times Earth's diameter, while the tail may stretch beyond one astronomical unit. If sufficiently bright, a comet may be seen from Earth without the aid of a telescope and may subtend an arc of 30 (60 Moons) across the sky. Comets have been observed and recorded since ancient times by many cultures and religions.

Comets usually have highly eccentric elliptical orbits, and they have a wide range of orbital periods, ranging from several years to potentially several millions of years. Short-period comets originate in the Kuiper belt or its associated scattered disc, which lie beyond the orbit of Neptune. Long-period comets are thought to originate in the Oort cloud, a spherical cloud of icy bodies extending from outside the Kuiper belt to halfway to the nearest star.[1] Long-period comets are set in motion towards the Sun from the Oort cloud by gravitational perturbations caused by passing stars and the galactic tide. Hyperbolic comets may pass once through the inner Solar System before being flung to interstellar space. The appearance of a comet is called an apparition.

Comets are distinguished from asteroids by the presence of an extended, gravitationally unbound atmosphere surrounding their central nucleus. This atmosphere has parts termed the coma (the central part immediately surrounding the nucleus) and the tail (a typically linear section consisting of dust or gas blown out from the coma by the Sun's light pressure or outstreaming solar wind plasma). However, extinct comets that have passed close to the Sun many times have lost nearly all of their volatile ices and dust and may come to resemble small asteroids.[2] Asteroids are thought to have a different origin from comets, having formed inside the orbit of Jupiter rather than in the outer Solar System.[3][4] The discovery of main-belt comets and active centaur minor planets has blurred the distinction between asteroids and comets. In the early 21st century, the discovery of some minor bodies with long-period comet orbits, but characteristics of inner solar system asteroids, were called Manx comets. They are still classified as comets, such as C/2014 S3 (PANSTARRS).[5] Twenty-seven Manx comets were found from 2013 to 2017.[6]

As of November2021[update] there are 4584 known comets.[7] However, this represents a very small fraction of the total potential comet population, as the reservoir of comet-like bodies in the outer Solar System (in the Oort cloud) is about one trillion.[8][9] Roughly one comet per year is visible to the naked eye, though many of those are faint and unspectacular.[10] Particularly bright examples are called "great comets". Comets have been visited by unmanned probes such as the European Space Agency's Rosetta, which became the first to land a robotic spacecraft on a comet,[11] and NASA's Deep Impact, which blasted a crater on Comet Tempel 1 to study its interior.

The word comet derives from the Old English cometa from the Latin comta or comts. That, in turn, is a romanization of the Greek 'wearing long hair', and the Oxford English Dictionary notes that the term () already meant 'long-haired star, comet' in Greek. was derived from (koman) 'to wear the hair long', which was itself derived from (kom) 'the hair of the head' and was used to mean 'the tail of a comet'.[12][13]

The astronomical symbol for comets (represented in Unicode) is U+2604 COMET, consisting of a small disc with three hairlike extensions.[14]

The solid, core structure of a comet is known as the nucleus. Cometary nuclei are composed of an amalgamation of rock, dust, water ice, and frozen carbon dioxide, carbon monoxide, methane, and ammonia.[15] As such, they are popularly described as "dirty snowballs" after Fred Whipple's model.[16] Comets with a higher dust content have been called "icy dirtballs".[17] The term "icy dirtballs" arose after observation of Comet 9P/Tempel 1 collision with an "impactor" probe sent by NASA Deep Impact mission in July 2005. Research conducted in 2014 suggests that comets are like "deep fried ice cream", in that their surfaces are formed of dense crystalline ice mixed with organic compounds, while the interior ice is colder and less dense.[18]

The surface of the nucleus is generally dry, dusty or rocky, suggesting that the ices are hidden beneath a surface crust several metres thick. In addition to the gases already mentioned, the nuclei contain a variety of organic compounds, which may include methanol, hydrogen cyanide, formaldehyde, ethanol, ethane, and perhaps more complex molecules such as long-chain hydrocarbons and amino acids.[19][20] In 2009, it was confirmed that the amino acid glycine had been found in the comet dust recovered by NASA's Stardust mission.[21] In August 2011, a report, based on NASA studies of meteorites found on Earth, was published suggesting DNA and RNA components (adenine, guanine, and related organic molecules) may have been formed on asteroids and comets.[22][23]

The outer surfaces of cometary nuclei have a very low albedo, making them among the least reflective objects found in the Solar System. The Giotto space probe found that the nucleus of Halley's Comet (1P/Halley) reflects about four percent of the light that falls on it,[24] and Deep Space 1 discovered that Comet Borrelly's surface reflects less than 3.0%;[24] by comparison, asphalt reflects seven percent. The dark surface material of the nucleus may consist of complex organic compounds. Solar heating drives off lighter volatile compounds, leaving behind larger organic compounds that tend to be very dark, like tar or crude oil. The low reflectivity of cometary surfaces causes them to absorb the heat that drives their outgassing processes.[25]

Comet nuclei with radii of up to 30 kilometers (19mi) have been observed,[26] but ascertaining their exact size is difficult.[27] The nucleus of 322P/SOHO is probably only 100200 meters (330660ft) in diameter.[28] A lack of smaller comets being detected despite the increased sensitivity of instruments has led some to suggest that there is a real lack of comets smaller than 100 meters (330ft) across.[29] Known comets have been estimated to have an average density of 0.6g/cm3 (0.35oz/cuin).[30] Because of their low mass, comet nuclei do not become spherical under their own gravity and therefore have irregular shapes.[31]

Roughly six percent of the near-Earth asteroids are thought to be the extinct nuclei of comets that no longer experience outgassing,[32] including 14827 Hypnos and 3552 Don Quixote.

Results from the Rosetta and Philae spacecraft show that the nucleus of 67P/ChuryumovGerasimenko has no magnetic field, which suggests that magnetism may not have played a role in the early formation of planetesimals.[33][34] Further, the ALICE spectrograph on Rosetta determined that electrons (within 1km (0.62mi) above the comet nucleus) produced from photoionization of water molecules by solar radiation, and not photons from the Sun as thought earlier, are responsible for the degradation of water and carbon dioxide molecules released from the comet nucleus into its coma.[35][36] Instruments on the Philae lander found at least sixteen organic compounds at the comet's surface, four of which (acetamide, acetone, methyl isocyanate and propionaldehyde) have been detected for the first time on a comet.[37][38][39]

The streams of dust and gas thus released form a huge and extremely thin atmosphere around the comet called the "coma". The force exerted on the coma by the Sun's radiation pressure and solar wind cause an enormous "tail" to form pointing away from the Sun.[48]

The coma is generally made of water and dust, with water making up to 90% of the volatiles that outflow from the nucleus when the comet is within 3 to 4 astronomical units (450,000,000 to 600,000,000km; 280,000,000 to 370,000,000mi) of the Sun.[49] The H2O parent molecule is destroyed primarily through photodissociation and to a much smaller extent photoionization, with the solar wind playing a minor role in the destruction of water compared to photochemistry.[49] Larger dust particles are left along the comet's orbital path whereas smaller particles are pushed away from the Sun into the comet's tail by light pressure.[50]

Although the solid nucleus of comets is generally less than 60 kilometers (37mi) across, the coma may be thousands or millions of kilometers across, sometimes becoming larger than the Sun.[51] For example, about a month after an outburst in October 2007, comet 17P/Holmes briefly had a tenuous dust atmosphere larger than the Sun.[52] The Great Comet of 1811 also had a coma roughly the diameter of the Sun.[53] Even though the coma can become quite large, its size can decrease about the time it crosses the orbit of Mars around 1.5 astronomical units (220,000,000km; 140,000,000mi) from the Sun.[53] At this distance the solar wind becomes strong enough to blow the gas and dust away from the coma, and in doing so enlarging the tail.[53] Ion tails have been observed to extend one astronomical unit (150million km) or more.[52]

Both the coma and tail are illuminated by the Sun and may become visible when a comet passes through the inner Solar System, the dust reflects sunlight directly while the gases glow from ionisation.[54] Most comets are too faint to be visible without the aid of a telescope, but a few each decade become bright enough to be visible to the naked eye.[55] Occasionally a comet may experience a huge and sudden outburst of gas and dust, during which the size of the coma greatly increases for a period of time. This happened in 2007 to Comet Holmes.[56]

In 1996, comets were found to emit X-rays.[57] This greatly surprised astronomers because X-ray emission is usually associated with very high-temperature bodies. The X-rays are generated by the interaction between comets and the solar wind: when highly charged solar wind ions fly through a cometary atmosphere, they collide with cometary atoms and molecules, "stealing" one or more electrons from the atom in a process called "charge exchange". This exchange or transfer of an electron to the solar wind ion is followed by its de-excitation into the ground state of the ion by the emission of X-rays and far ultraviolet photons.[58]

Bow shocks form as a result of the interaction between the solar wind and the cometary ionosphere, which is created by the ionization of gases in the coma. As the comet approaches the Sun, increasing outgassing rates cause the coma to expand, and the sunlight ionizes gases in the coma. When the solar wind passes through this ion coma, the bow shock appears.

The first observations were made in the 1980s and 1990s as several spacecraft flew by comets 21P/GiacobiniZinner,[59] 1P/Halley,[60] and 26P/GriggSkjellerup.[61] It was then found that the bow shocks at comets are wider and more gradual than the sharp planetary bow shocks seen at, for example, Earth. These observations were all made near perihelion when the bow shocks already were fully developed.

The Rosetta spacecraft observed the bow shock at comet 67P/ChuryumovGerasimenko at an early stage of bow shock development when the outgassing increased during the comet's journey toward the Sun. This young bow shock was called the "infant bow shock". The infant bow shock is asymmetric and, relative to the distance to the nucleus, wider than fully developed bow shocks.[62]

In the outer Solar System, comets remain frozen and inactive and are extremely difficult or impossible to detect from Earth due to their small size. Statistical detections of inactive comet nuclei in the Kuiper belt have been reported from observations by the Hubble Space Telescope[63][64] but these detections have been questioned.[65][66] As a comet approaches the inner Solar System, solar radiation causes the volatile materials within the comet to vaporize and stream out of the nucleus, carrying dust away with them.

The streams of dust and gas each form their own distinct tail, pointing in slightly different directions. The tail of dust is left behind in the comet's orbit in such a manner that it often forms a curved tail called the type II or dust tail.[54] At the same time, the ion or type I tail, made of gases, always points directly away from the Sun because this gas is more strongly affected by the solar wind than is dust, following magnetic field lines rather than an orbital trajectory.[67] On occasionssuch as when Earth passes through a comet's orbital plane, the antitail, pointing in the opposite direction to the ion and dust tails, may be seen.[68]

The observation of antitails contributed significantly to the discovery of solar wind.[69] The ion tail is formed as a result of the ionization by solar ultra-violet radiation of particles in the coma. Once the particles have been ionized, they attain a net positive electrical charge, which in turn gives rise to an "induced magnetosphere" around the comet. The comet and its induced magnetic field form an obstacle to outward flowing solar wind particles. Because the relative orbital speed of the comet and the solar wind is supersonic, a bow shock is formed upstream of the comet in the flow direction of the solar wind. In this bow shock, large concentrations of cometary ions (called "pick-up ions") congregate and act to "load" the solar magnetic field with plasma, such that the field lines "drape" around the comet forming the ion tail.[70]

If the ion tail loading is sufficient, the magnetic field lines are squeezed together to the point where, at some distance along the ion tail, magnetic reconnection occurs. This leads to a "tail disconnection event".[70] This has been observed on a number of occasions, one notable event being recorded on 20 April 2007, when the ion tail of Encke's Comet was completely severed while the comet passed through a coronal mass ejection. This event was observed by the STEREO space probe.[71]

In 2013, ESA scientists reported that the ionosphere of the planet Venus streams outwards in a manner similar to the ion tail seen streaming from a comet under similar conditions."[72][73]

Uneven heating can cause newly generated gases to break out of a weak spot on the surface of comet's nucleus, like a geyser.[74] These streams of gas and dust can cause the nucleus to spin, and even split apart.[74] In 2010 it was revealed dry ice (frozen carbon dioxide) can power jets of material flowing out of a comet nucleus.[75] Infrared imaging of Hartley2 shows such jets exiting and carrying with it dust grains into the coma.[76]

Most comets are small Solar System bodies with elongated elliptical orbits that take them close to the Sun for a part of their orbit and then out into the further reaches of the Solar System for the remainder.[77] Comets are often classified according to the length of their orbital periods: The longer the period the more elongated the ellipse.

Periodic comets or short-period comets are generally defined as those having orbital periods of less than 200 years.[78] They usually orbit more-or-less in the ecliptic plane in the same direction as the planets.[79] Their orbits typically take them out to the region of the outer planets (Jupiter and beyond) at aphelion; for example, the aphelion of Halley's Comet is a little beyond the orbit of Neptune. Comets whose aphelia are near a major planet's orbit are called its "family".[80] Such families are thought to arise from the planet capturing formerly long-period comets into shorter orbits.[81]

At the shorter orbital period extreme, Encke's Comet has an orbit that does not reach the orbit of Jupiter, and is known as an Encke-type comet. Short-period comets with orbital periods less than 20 years and low inclinations (up to 30 degrees) to the ecliptic are called traditional Jupiter-family comets (JFCs).[82][83] Those like Halley, with orbital periods of between 20 and 200 years and inclinations extending from zero to more than 90 degrees, are called Halley-type comets (HTCs).[84][85] As of 2022[update], 94 HTCs have been observed,[86] compared with 744 identified JFCs.[87]

Recently discovered main-belt comets form a distinct class, orbiting in more circular orbits within the asteroid belt.[88][89]

Because their elliptical orbits frequently take them close to the giant planets, comets are subject to further gravitational perturbations.[90] Short-period comets have a tendency for their aphelia to coincide with a giant planet's semi-major axis, with the JFCs being the largest group.[83] It is clear that comets coming in from the Oort cloud often have their orbits strongly influenced by the gravity of giant planets as a result of a close encounter. Jupiter is the source of the greatest perturbations, being more than twice as massive as all the other planets combined. These perturbations can deflect long-period comets into shorter orbital periods.[91][92]

Based on their orbital characteristics, short-period comets are thought to originate from the centaurs and the Kuiper belt/scattered disc[93] a disk of objects in the trans-Neptunian regionwhereas the source of long-period comets is thought to be the far more distant spherical Oort cloud (after the Dutch astronomer Jan Hendrik Oort who hypothesized its existence).[94] Vast swarms of comet-like bodies are thought to orbit the Sun in these distant regions in roughly circular orbits. Occasionally the gravitational influence of the outer planets (in the case of Kuiper belt objects) or nearby stars (in the case of Oort cloud objects) may throw one of these bodies into an elliptical orbit that takes it inwards toward the Sun to form a visible comet. Unlike the return of periodic comets, whose orbits have been established by previous observations, the appearance of new comets by this mechanism is unpredictable.[95] When flung into the orbit of the sun, and being continuously dragged towards it, tons of matter are stripped from the comets which greatly influence their lifetime; the more stripped, the shorter they live and vice versa.[96]

Long-period comets have highly eccentric orbits and periods ranging from 200 years to thousands or even millions of years.[97] An eccentricity greater than 1 when near perihelion does not necessarily mean that a comet will leave the Solar System.[98] For example, Comet McNaught had a heliocentric osculating eccentricity of 1.000019 near its perihelion passage epoch in January 2007 but is bound to the Sun with roughly a 92,600-year orbit because the eccentricity drops below 1 as it moves farther from the Sun. The future orbit of a long-period comet is properly obtained when the osculating orbit is computed at an epoch after leaving the planetary region and is calculated with respect to the center of mass of the Solar System. By definition long-period comets remain gravitationally bound to the Sun; those comets that are ejected from the Solar System due to close passes by major planets are no longer properly considered as having "periods". The orbits of long-period comets take them far beyond the outer planets at aphelia, and the plane of their orbits need not lie near the ecliptic. Long-period comets such as C/1999 F1 and C/2017 T2 (PANSTARRS) can have aphelion distances of nearly 70,000AU (0.34pc; 1.1ly) with orbital periods estimated around 6million years.

Single-apparition or non-periodic comets are similar to long-period comets because they also have parabolic or slightly hyperbolic trajectories[97] when near perihelion in the inner Solar System. However, gravitational perturbations from giant planets cause their orbits to change. Single-apparition comets have a hyperbolic or parabolic osculating orbit which allows them to permanently exit the Solar System after a single pass of the Sun.[99] The Sun's Hill sphere has an unstable maximum boundary of 230,000AU (1.1pc; 3.6ly).[100] Only a few hundred comets have been seen to reach a hyperbolic orbit (e > 1) when near perihelion[101] that using a heliocentric unperturbed two-body best-fit suggests they may escape the Solar System.

As of 2022[update], only two objects have been discovered with an eccentricity significantly greater than one: 1I/Oumuamua and 2I/Borisov, indicating an origin outside the Solar System. While Oumuamua, with an eccentricity of about 1.2, showed no optical signs of cometary activity during its passage through the inner Solar System in October 2017, changes to its trajectorywhich suggests outgassingindicate that it is probably a comet.[102] On the other hand, 2I/Borisov, with an estimated eccentricity of about 3.36, has been observed to have the coma feature of comets, and is considered the first detected interstellar comet.[103][104] Comet C/1980 E1 had an orbital period of roughly 7.1million years before the 1982 perihelion passage, but a 1980 encounter with Jupiter accelerated the comet giving it the largest eccentricity (1.057) of any known solar comet with a reasonable observation arc.[105] Comets not expected to return to the inner Solar System include C/1980 E1, C/2000 U5, C/2001 Q4 (NEAT), C/2009 R1, C/1956 R1, and C/2007 F1 (LONEOS).

Some authorities use the term "periodic comet" to refer to any comet with a periodic orbit (that is, all short-period comets plus all long-period comets),[106] whereas others use it to mean exclusively short-period comets.[97] Similarly, although the literal meaning of "non-periodic comet" is the same as "single-apparition comet", some use it to mean all comets that are not "periodic" in the second sense (that is, to also include all comets with a period greater than 200 years).

Early observations have revealed a few genuinely hyperbolic (i.e. non-periodic) trajectories, but no more than could be accounted for by perturbations from Jupiter. Comets from interstellar space are moving with velocities of the same order as the relative velocities of stars near the Sun (a few tens of km per second). When such objects enter the Solar System, they have a positive specific orbital energy resulting in a positive velocity at infinity ( v {displaystyle v_{infty }!} ) and have notably hyperbolic trajectories. A rough calculation shows that there might be four hyperbolic comets per century within Jupiter's orbit, give or take one and perhaps two orders of magnitude.[107]

The Oort cloud is thought to occupy a vast space starting from between 2,000 and 5,000AU (0.03 and 0.08ly)[109] to as far as 50,000AU (0.79ly)[84] from the Sun. This cloud encases the celestial bodies that start at the middle of the Solar Systemthe Sun, all the way to outer limits of the Kuiper Belt. The Oort cloud consists of viable materials necessary for the creation of celestial bodies. The Solar System's planets exist only because of the planetesimals (chunks of leftover space that assisted in the creation of planets) that were condensed and formed by the gravity of the Sun. The eccentric made from these trapped planetesimals is why the Oort Cloud even exists.[110] Some estimates place the outer edge at between 100,000 and 200,000AU (1.58 and 3.16ly).[109] The region can be subdivided into a spherical outer Oort cloud of 20,00050,000AU (0.320.79ly), and a doughnut-shaped inner cloud, the Hills cloud, of 2,00020,000AU (0.030.32ly).[111] The outer cloud is only weakly bound to the Sun and supplies the long-period (and possibly Halley-type) comets that fall to inside the orbit of Neptune.[84] The inner Oort cloud is also known as the Hills cloud, named after J. G. Hills, who proposed its existence in 1981.[112] Models predict that the inner cloud should have tens or hundreds of times as many cometary nuclei as the outer halo;[112][113][114] it is seen as a possible source of new comets that resupply the relatively tenuous outer cloud as the latter's numbers are gradually depleted. The Hills cloud explains the continued existence of the Oort cloud after billions of years.[115]

Exocomets beyond the Solar System have also been detected and may be common in the Milky Way.[116] The first exocomet system detected was around Beta Pictoris, a very young A-type main-sequence star, in 1987.[117][118] A total of 11 such exocomet systems have been identified as of 2013[update], using the absorption spectrum caused by the large clouds of gas emitted by comets when passing close to their star.[116][117] For ten years the Kepler space telescope was responsible for searching for planets and other forms outside of the solar system. The first transiting exocomets were found in February 2018 by a group consisting of professional astronomers and citizen scientists in light curves recorded by the Kepler Space Telescope.[119][120] After Kepler Space Telescope retired in October 2018, a new telescope called TESS Telescope has taken over Kepler's mission. Since the launch of TESS, astronomers have discovered the transits of comets around the star Beta Pictoris using a light curve from TESS.[121][122] Since TESS has taken over, astronomers have since been able to better distinguish exocomets with the spectroscopic method. New planets are detected by the white light curve method which is viewed as a symmetrical dip in the charts readings when a planet overshadows its parent star. However, after further evaluation of these light curves, it has been discovered that the asymmetrical patterns of the dips presented are caused by the tail of a comet or of hundreds of comets.[123]

As a comet is heated during close passes to the Sun, outgassing of its icy components also releases solid debris too large to be swept away by radiation pressure and the solar wind.[124] If Earth's orbit sends it through that trail of debris, which is composed mostly of fine grains of rocky material, there is likely to be a meteor shower as Earth passes through. Denser trails of debris produce quick but intense meteor showers and less dense trails create longer but less intense showers. Typically, the density of the debris trail is related to how long ago the parent comet released the material.[125][126] The Perseid meteor shower, for example, occurs every year between 9 and 13 August, when Earth passes through the orbit of Comet SwiftTuttle. Halley's Comet is the source of the Orionid shower in October.[127][128]

Many comets and asteroids collided with Earth in its early stages. Many scientists think that comets bombarding the young Earth about 4billion years ago brought the vast quantities of water that now fill Earth's oceans, or at least a significant portion of it. Others have cast doubt on this idea.[129] The detection of organic molecules, including polycyclic aromatic hydrocarbons,[18] in significant quantities in comets has led to speculation that comets or meteorites may have brought the precursors of lifeor even life itselfto Earth.[130] In 2013 it was suggested that impacts between rocky and icy surfaces, such as comets, had the potential to create the amino acids that make up proteins through shock synthesis.[131] The speed at which the comets entered the atmosphere, combined with the magnitude of energy created after initial contact, allowed smaller molecules to condense into the larger macro-molecules that served as the foundation for life.[132] In 2015, scientists found significant amounts of molecular oxygen in the outgassings of comet 67P, suggesting that the molecule may occur more often than had been thought, and thus less an indicator of life as has been supposed.[133]

It is suspected that comet impacts have, over long timescales, also delivered significant quantities of water to Earth's Moon, some of which may have survived as lunar ice.[134] Comet and meteoroid impacts are also thought to be responsible for the existence of tektites and australites.[135]

Fear of comets as acts of God and signs of impending doom was highest in Europe from AD 1200 to 1650.[136] The year after the Great Comet of 1618, for example, Gotthard Arthusius published a pamphlet stating that it was a sign that the Day of Judgment was near.[137] He listed ten pages of comet-related disasters, including "earthquakes, floods, changes in river courses, hail storms, hot and dry weather, poor harvests, epidemics, war and treason and high prices".[136]

By 1700 most scholars concluded that such events occurred whether a comet was seen or not. Using Edmond Halley's records of comet sightings, however, William Whiston in 1711 wrote that the Great Comet of 1680 had a periodicity of 574 years and was responsible for the worldwide flood in the Book of Genesis, by pouring water on Earth. His announcement revived for another century fear of comets, now as direct threats to the world instead of signs of disasters.[136] Spectroscopic analysis in 1910 found the toxic gas cyanogen in the tail of Halley's Comet,[138] causing panicked buying of gas masks and quack "anti-comet pills" and "anti-comet umbrellas" by the public.[139]

If a comet is traveling fast enough, it may leave the Solar System. Such comets follow the open path of a hyperbola, and as such, they are called hyperbolic comets. Solar comets are only known to be ejected by interacting with another object in the Solar System, such as Jupiter.[140] An example of this is Comet C/1980 E1, which was shifted from an orbit of 7.1million years around the Sun, to a hyperbolic trajectory, after a 1980 close pass by the planet Jupiter.[141] Interstellar comets such as 1I/Oumuamua and 2I/Borisov never orbited the Sun and therefore do not require a 3rd-body interaction to be ejected from the Solar System.

Jupiter-family comets and long-period comets appear to follow very different fading laws. The JFCs are active over a lifetime of about 10,000 years or ~1,000 orbits whereas long-period comets fade much faster. Only 10% of the long-period comets survive more than 50 passages to small perihelion and only 1% of them survive more than 2,000 passages.[32] Eventually most of the volatile material contained in a comet nucleus evaporates, and the comet becomes a small, dark, inert lump of rock or rubble that can resemble an asteroid.[142] Some asteroids in elliptical orbits are now identified as extinct comets.[143][144][145][146] Roughly six percent of the near-Earth asteroids are thought to be extinct comet nuclei.[32]

The nucleus of some comets may be fragile, a conclusion supported by the observation of comets splitting apart.[147] A significant cometary disruption was that of Comet ShoemakerLevy 9, which was discovered in 1993. A close encounter in July 1992 had broken it into pieces, and over a period of six days in July 1994, these pieces fell into Jupiter's atmospherethe first time astronomers had observed a collision between two objects in the Solar System.[148][149] Other splitting comets include 3D/Biela in 1846 and 73P/SchwassmannWachmann from 1995 to 2006.[150] Greek historian Ephorus reported that a comet split apart as far back as the winter of 372373 BC.[151] Comets are suspected of splitting due to thermal stress, internal gas pressure, or impact.[152]

Comets 42P/Neujmin and 53P/Van Biesbroeck appear to be fragments of a parent comet. Numerical integrations have shown that both comets had a rather close approach to Jupiter in January 1850, and that, before 1850, the two orbits were nearly identical.[153]

Some comets have been observed to break up during their perihelion passage, including great comets West and IkeyaSeki. Biela's Comet was one significant example when it broke into two pieces during its passage through the perihelion in 1846. These two comets were seen separately in 1852, but never again afterward. Instead, spectacular meteor showers were seen in 1872 and 1885 when the comet should have been visible. A minor meteor shower, the Andromedids, occurs annually in November, and it is caused when Earth crosses the orbit of Biela's Comet.[154]

Some comets meet a more spectacular end either falling into the Sun[155] or smashing into a planet or other body. Collisions between comets and planets or moons were common in the early Solar System: some of the many craters on the Moon, for example, may have been caused by comets. A recent collision of a comet with a planet occurred in July 1994 when Comet ShoemakerLevy 9 broke up into pieces and collided with Jupiter.[156]

Ghost tail of C/2015 D1 (SOHO) after passage at the Sun

The names given to comets have followed several different conventions over the past two centuries. Prior to the early 20th century, most comets were referred to by the year when they appeared, sometimes with additional adjectives for particularly bright comets; thus, the "Great Comet of 1680", the "Great Comet of 1882", and the "Great January Comet of 1910".

After Edmond Halley demonstrated that the comets of 1531, 1607, and 1682 were the same body and successfully predicted its return in 1759 by calculating its orbit, that comet became known as Halley's Comet.[158] Similarly, the second and third known periodic comets, Encke's Comet[159] and Biela's Comet,[160] were named after the astronomers who calculated their orbits rather than their original discoverers. Later, periodic comets were usually named after their discoverers, but comets that had appeared only once continued to be referred to by the year of their appearance.[161]

In the early 20th century, the convention of naming comets after their discoverers became common, and this remains so today. A comet can be named after its discoverers or an instrument or program that helped to find it.[161] For example, in 2019, astronomer Gennadiy Borisov observed a comet that appeared to have originated outside of the solar system; the comet was named 2I/Borisov after him.[162]

From ancient sources, such as Chinese oracle bones, it is known that comets have been noticed by humans for millennia.[163] Until the sixteenth century, comets were usually considered bad omens of deaths of kings or noble men, or coming catastrophes, or even interpreted as attacks by heavenly beings against terrestrial inhabitants.[164][165]

Aristotle (384322 BC) was the first known scientist to use various theories and observational facts to employ a consistent, structured cosmological theory of comets. He believed that comets were atmospheric phenomena, due to the fact that they could appear outside of the zodiac and vary in brightness over the course of a few days. Aristotle's cometary theory arose from his observations and cosmological theory that everything in the cosmos is arranged in a distinct configuration.[166] Part of this configuration was a clear separation between the celestial and terrestrial, believing comets to be strictly associated with the latter. According to Aristotle, comets must be within the sphere of the moon and clearly separated from the heavens. Also in the 4th century BC, Apollonius of Myndus supported the idea that comets moved like the planets.[167] Aristotelian theory on comets continued to be widely accepted throughout the Middle Ages, despite several discoveries from various individuals challenging aspects of it.[168]

In the 1st century AD, Seneca the Younger questioned Aristotle's logic concerning comets. Because of their regular movement and imperviousness to wind, they cannot be atmospheric,[169] and are more permanent than suggested by their brief flashes across the sky.[a] He pointed out that only the tails are transparent and thus cloudlike, and argued that there is no reason to confine their orbits to the zodiac.[169] In criticizing Apollonius of Myndus, Seneca argues, "A comet cuts through the upper regions of the universe and then finally becomes visible when it reaches the lowest point of its orbit."[170] While Seneca did not author a substantial theory of his own,[171] his arguments would spark much debate among Aristotle's critics in the 16th and 17th centuries.[168][b]

Also in the 1st century, Pliny the Elder believed that comets were connected with political unrest and death.[173] Pliny observed comets as "human like", often describing their tails with "long hair" or "long beard".[174] His system for classifying comets according to their color and shape was used for centuries.[175]

In India, by the 6th century astronomers believed that comets were celestial bodies that re-appeared periodically. This was the view expressed in the 6th century by the astronomers Varhamihira and Bhadrabahu, and the 10th-century astronomer Bhaotpala listed the names and estimated periods of certain comets, but it is not known how these figures were calculated or how accurate they were.[176] In 1301, the Italian painter Giotto was the first person to accurately and anatomically portray a comet. In his work Adoration of the Magi, Giotto's depiction of Halley's Comet in the place of the Star of Bethlehem would go unmatched in accuracy until the 19th century and be bested only with the invention of photography.[177]

Astrological interpretations of comets proceeded to take precedence clear into the 15th century, despite the presence of modern scientific astronomy beginning to take root. Comets continued to forewarn of disaster, as seen in the Luzerner Schilling chronicles and in the warnings of Pope Callixtus III.[177] In 1578, German Lutheran bishop Andreas Celichius defined comets as "the thick smoke of human sins... kindled by the hot and fiery anger of the Supreme Heavenly Judge". The next year, Andreas Dudith stated that "If comets were caused by the sins of mortals, they would never be absent from the sky."[178]

Crude attempts at a parallax measurement of Halley's Comet were made in 1456, but were erroneous.[179] Regiomontanus was the first to attempt to calculate diurnal parallax by observing the great comet of 1472. His predictions were not very accurate, but they were conducted in the hopes of estimating the distance of a comet from Earth.[175]

In the 16th century, Tycho Brahe and Michael Maestlin demonstrated that comets must exist outside of Earth's atmosphere by measuring the parallax of the Great Comet of 1577.[180] Within the precision of the measurements, this implied the comet must be at least four times more distant than from Earth to the Moon.[181][182] Based on observations in 1664, Giovanni Borelli recorded the longitudes and latitudes of comets that he observed, and suggested that cometary orbits may be parabolic.[183] Galileo Galilei, one of the most renowned astronomers to date, even attempted writings on comets in The Assayer. He rejected Brahe's theories on the parallax of comets and claimed that they may be a mere optical illusion. Intrigued as early scientists were about the nature of comets, Galileo presented his own theories despite little personal observation.[175] Maestlin's student Johannes Kepler responded to these unjust criticisms in his work Hyperaspistes. Jakob Bernoulli published another attempt to explain comets (Conamen Novi Systematis Cometarum) in 1682.

Also occurring in the early modern period was the study of comets and their astrological significance in medical disciplines. Many healers of this time considered medicine and astronomy to be inter-disciplinary and employed their knowledge of comets and other astrological signs for diagnosing and treating patients.[184]

Isaac Newton, in his Principia Mathematica of 1687, proved that an object moving under the influence of gravity by an inverse square law must trace out an orbit shaped like one of the conic sections, and he demonstrated how to fit a comet's path through the sky to a parabolic orbit, using the comet of 1680 as an example.[185]He describes comets as compact and durable solid bodies moving in oblique orbit and their tails as thin streams of vapor emitted by their nuclei, ignited or heated by the Sun. He suspected that comets were the origin of the life-supporting component of air.[186] He also pointed out that comets usually appear near the Sun, and therefore most likely orbit it.[169] On their luminosity, he stated, "The comets shine by the Sun's light, which they reflect," with their tails illuminated by "the Sun's light reflected by a smoke arising from [the coma]".[169]

In 1705, Edmond Halley (16561742) applied Newton's method to 23 cometary apparitions that had occurred between 1337 and 1698. He noted that three of these, the comets of 1531, 1607, and 1682, had very similar orbital elements, and he was further able to account for the slight differences in their orbits in terms of gravitational perturbation caused by Jupiter and Saturn. Confident that these three apparitions had been three appearances of the same comet, he predicted that it would appear again in 175859.[187] Halley's predicted return date was later refined by a team of three French mathematicians: Alexis Clairaut, Joseph Lalande, and Nicole-Reine Lepaute, who predicted the date of the comet's 1759 perihelion to within one month's accuracy.[188][189] When the comet returned as predicted, it became known as Halley's Comet.[190]

From his huge vapouring train perhaps to shakeReviving moisture on the numerous orbs,Thro' which his long ellipsis winds; perhapsTo lend new fuel to declining suns,To light up worlds, and feed th' ethereal fire.

James Thomson The Seasons (1730; 1748)[191]

As early as the 18th century, some scientists had made correct hypotheses as to comets' physical composition. In 1755, Immanuel Kant hypothesized in his Universal Natural History that comets were condensed from "primitive matter" beyond the known planets, which is "feebly moved" by gravity, then orbit at arbitrary inclinations, and are partially vaporized by the Sun's heat as they near perihelion.[192] In 1836, the German mathematician Friedrich Wilhelm Bessel, after observing streams of vapor during the appearance of Halley's Comet in 1835, proposed that the jet forces of evaporating material could be great enough to significantly alter a comet's orbit, and he argued that the non-gravitational movements of Encke's Comet resulted from this phenomenon.[193]

In the 19th century, the Astronomical Observatory of Padova was an epicenter in the observational study of comets. Led by Giovanni Santini (17871877) and followed by Giuseppe Lorenzoni (18431914), this observatory was devoted to classical astronomy, mainly to the new comets and planets orbit calculation, with the goal of compiling a catalog of almost ten thousand stars. Situated in the Northern portion of Italy, observations from this observatory were key in establishing important geodetic, geographic, and astronomical calculations, such as the difference of longitude between Milan and Padua as well as Padua to Fiume.[194] In addition to these geographic observations, correspondence within the observatory, particularly between Santini and another astronomer Giuseppe Toaldo, about the importance of comet and planetary orbital observations.[195]

In 1950, Fred Lawrence Whipple proposed that rather than being rocky objects containing some ice, comets were icy objects containing some dust and rock.[196] This "dirty snowball" model soon became accepted and appeared to be supported by the observations of an armada of spacecraft (including the European Space Agency's Giotto probe and the Soviet Union's Vega 1 and Vega 2) that flew through the coma of Halley's Comet in 1986, photographed the nucleus, and observed jets of evaporating material.[197]

On 22 January 2014, ESA scientists reported the detection, for the first definitive time, of water vapor on the dwarf planet Ceres, the largest object in the asteroid belt.[198] The detection was made by using the far-infrared abilities of the Herschel Space Observatory.[199] The finding is unexpected because comets, not asteroids, are typically considered to "sprout jets and plumes". According to one of the scientists, "The lines are becoming more and more blurred between comets and asteroids."[199] On 11 August 2014, astronomers released studies, using the Atacama Large Millimeter/Submillimeter Array (ALMA) for the first time, that detailed the distribution of HCN, HNC, H2CO, and dust inside the comae of comets C/2012 F6 (Lemmon) and C/2012 S1 (ISON).[200][201]

Approximately once a decade, a comet becomes bright enough to be noticed by a casual observer, leading such comets to be designated as great comets.[151] Predicting whether a comet will become a great comet is notoriously difficult, as many factors may cause a comet's brightness to depart drastically from predictions.[210] Broadly speaking, if a comet has a large and active nucleus, will pass close to the Sun, and is not obscured by the Sun as seen from Earth when at its brightest, it has a chance of becoming a great comet. However, Comet Kohoutek in 1973 fulfilled all the criteria and was expected to become spectacular but failed to do so.[211] Comet West, which appeared three years later, had much lower expectations but became an extremely impressive comet.[212]

The Great Comet of 1577 is a well-known example of a great comet. It passed near Earth as a non-periodic comet and was seen by many, including well-known astronomers Tycho Brahe and Taqi ad-Din. Observations of this comet led to several significant findings regarding cometary science, especially for Brahe.

The late 20th century saw a lengthy gap without the appearance of any great comets, followed by the arrival of two in quick successionComet Hyakutake in 1996, followed by HaleBopp, which reached maximum brightness in 1997 having been discovered two years earlier. The first great comet of the 21st century was C/2006 P1 (McNaught), which became visible to naked eye observers in January 2007. It was the brightest in over 40 years.[213]

A sungrazing comet is a comet that passes extremely close to the Sun at perihelion, generally within a few million kilometers.[214] Although small sungrazers can be completely evaporated during such a close approach to the Sun, larger sungrazers can survive many perihelion passages. However, the strong tidal forces they experience often lead to their fragmentation.[215]

About 90% of the sungrazers observed with SOHO are members of the Kreutz group, which all originate from one giant comet that broke up into many smaller comets during its first passage through the inner Solar System.[216] The remainder contains some sporadic sungrazers, but four other related groups of comets have been identified among them: the Kracht, Kracht 2a, Marsden, and Meyer groups. The Marsden and Kracht groups both appear to be related to Comet 96P/Machholz, which is also the parent of two meteor streams, the Quadrantids and the Arietids.[217]

Of the thousands of known comets, some exhibit unusual properties. Comet Encke (2P/Encke) orbits from outside the asteroid belt to just inside the orbit of the planet Mercury whereas the Comet 29P/SchwassmannWachmann currently travels in a nearly circular orbit entirely between the orbits of Jupiter and Saturn.[218] 2060 Chiron, whose unstable orbit is between Saturn and Uranus, was originally classified as an asteroid until a faint coma was noticed.[219] Similarly, Comet ShoemakerLevy 2 was originally designated asteroid 1990 UL3.[220]

The largest known periodic comet is 95P/Chiron at 200km in diameter that comes to perihelion every 50 years just inside of Saturn's orbit at 8 AU. The largest known Oort cloud comet is suspected of being Comet Bernardinelli-Bernstein at 150km that will not come to perihelion until January 2031 just outside of Saturn's orbit at 11 AU. The Comet of 1729 is estimated to have been 100km in diameter and came to perihelion inside of Jupiter's orbit at 4 AU.

Centaurs typically behave with characteristics of both asteroids and comets.[221] Centaurs can be classified as comets such as 60558 Echeclus, and 166P/NEAT. 166P/NEAT was discovered while it exhibited a coma, and so is classified as a comet despite its orbit, and 60558 Echeclus was discovered without a coma but later became active,[222] and was then classified as both a comet and an asteroid (174P/Echeclus). One plan for Cassini involved sending it to a centaur, but NASA decided to destroy it instead.[223]

A comet may be discovered photographically using a wide-field telescope or visually with binoculars. However, even without access to optical equipment, it is still possible for the amateur astronomer to discover a sungrazing comet online by downloading images accumulated by some satellite observatories such as SOHO.[224] SOHO's 2000th comet was discovered by Polish amateur astronomer Micha Kusiak on 26 December 2010[225] and both discoverers of HaleBopp used amateur equipment (although Hale was not an amateur).

A number of periodic comets discovered in earlier decades or previous centuries are now lost comets. Their orbits were never known well enough to predict future appearances or the comets have disintegrated. However, occasionally a "new" comet is discovered, and calculation of its orbit shows it to be an old "lost" comet. An example is Comet 11P/TempelSwiftLINEAR, discovered in 1869 but unobservable after 1908 because of perturbations by Jupiter. It was not found again until accidentally rediscovered by LINEAR in 2001.[226] There are at least 18 comets that fit this category.[227]

The depiction of comets in popular culture is firmly rooted in the long Western tradition of seeing comets as harbingers of doom and as omens of world-altering change.[228] Halley's Comet alone has caused a slew of sensationalist publications of all sorts at each of its reappearances. It was especially noted that the birth and death of some notable persons coincided with separate appearances of the comet, such as with writers Mark Twain (who correctly speculated that he'd "go out with the comet" in 1910)[228] and Eudora Welty, to whose life Mary Chapin Carpenter dedicated the song "Halley Came to Jackson".[228]

In times past, bright comets often inspired panic and hysteria in the general population, being thought of as bad omens. More recently, during the passage of Halley's Comet in 1910, Earth passed through the comet's tail, and erroneous newspaper reports inspired a fear that cyanogen in the tail might poison millions,[229] whereas the appearance of Comet HaleBopp in 1997 triggered the mass suicide of the Heaven's Gate cult.[230]

In science fiction, the impact of comets has been depicted as a threat overcome by technology and heroism (as in the 1998 films Deep Impact and Armageddon), or as a trigger of global apocalypse (Lucifer's Hammer, 1979) or zombies (Night of the Comet, 1984).[228] In Jules Verne's Off on a Comet a group of people are stranded on a comet orbiting the Sun, while a large crewed space expedition visits Halley's Comet in Sir Arthur C. Clarke's novel 2061: Odyssey Three.[231]

The long-period comet first recorded by Pons in Florence on 15 July 1825 inspired Lydia Sigourney's humorous poem The Comet of 1825. in which all the celestial bodies argue over the comet's appearance and purpose.

NASA is developing a comet harpoon for returning samples to Earth

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Comet - Wikipedia

Comet | Definition, Composition, & Facts | Britannica

Summary

comet, a small body orbiting the Sun with a substantial fraction of its composition made up of volatile ices. When a comet comes close to the Sun, the ices sublimate (go directly from the solid to the gas phase) and form, along with entrained dust particles, a bright outflowing atmosphere around the comet nucleus known as a coma. As dust and gas in the coma flow freely into space, the comet forms two tails, one composed of ionized molecules and radicals and one of dust. The word comet comes from the Greek (kometes), which means long-haired. Indeed, it is the appearance of the bright coma that is the standard observational test for whether a newly discovered object is a comet or an asteroid.

Comets are among the most-spectacular objects in the sky, with their bright glowing comae and their long dust tails and ion tails. Comets can appear at random from any direction and provide a fabulous and ever-changing display for many months as they move in highly eccentric orbits around the Sun.

Comets are important to scientists because they are primitive bodies left over from the formation of the solar system. They were among the first solid bodies to form in the solar nebula, the collapsing interstellar cloud of dust and gas out of which the Sun and planets formed. Comets formed in the outer regions of the solar nebula where it was cold enough for volatile ices to condense. This is generally taken to be beyond 5 astronomical units (AU; 748 million km, or 465 million miles), or beyond the orbit of Jupiter. Because comets have been stored in distant orbits beyond the planets, they have undergone few of the modifying processes that have melted or changed the larger bodies in the solar system. Thus, they retain a physical and chemical record of the primordial solar nebula and of the processes involved in the formation of planetary systems.

A comet is made up of four visible parts: the nucleus, the coma, the ion tail, and the dust tail. The nucleus is a solid body typically a few kilometres in diameter and made up of a mixture of volatile ices (predominantly water ice) and silicate and organic dust particles. The coma is the freely escaping atmosphere around the nucleus that forms when the comet comes close to the Sun and the volatile ices sublimate, carrying with them dust particles that are intimately mixed with the frozen ices in the nucleus. The dust tail forms from those dust particles and is blown back by solar radiation pressure to form a long curving tail that is typically white or yellow in colour. The ion tail forms from the volatile gases in the coma when they are ionized by ultraviolet photons from the Sun and blown away by the solar wind. Ion tails point almost exactly away from the Sun and glow bluish in colour because of the presence of CO+ ions.

Comets differ from other bodies in the solar system in that they are generally in orbits that are far more eccentric than those of the planets and most asteroids and far more inclined to the ecliptic (the plane of Earths orbit). Some comets appear to come from distances of over 50,000 AU, a substantial fraction of the distance to the nearest stars. Their orbital periods can be millions of years in length. Other comets have shorter periods and smaller orbits that carry them from the orbits of Jupiter and Saturn inward to the orbits of the terrestrial planets. Some comets even appear to come from interstellar space, passing around the Sun on open, hyperbolic orbits, but in fact are members of the solar system.

Comets are typically named for their discoverers, though some comets (e.g., Halley and Encke) are named for the scientists who first recognized that their orbits were periodic. The International Astronomical Union (IAU) prefers a maximum of two discoverers to be in a comets name. In some cases where a comet has been lost (its orbit was not determined well enough to predict its return), the comet is named for the original discoverer and also the observer(s) who found it again. A designation of C/ before a comets name denotes that it is a long-period comet (period greater than 200 years), while P/ denotes that the comet is periodic; i.e., it returns at regular, predictable intervals of fewer than 200 years. A designation of D/ denotes that the comet is deceased or destroyed, such as D/Shoemaker-Levy 9, the comet whose components struck Jupiter in July 1994. Numbers appearing before the name of a comet denote that it is periodic; the comets are numbered in the order that they are confirmed to be periodic. Comet 1P/Halley is the first comet to be recognized as periodic and is named after English astronomer Edmond Halley, who determined that it was periodic.

In 1995 the IAU implemented a new identification system for each appearance of a comet, whether it is periodic or long-period. The system uses the year of the comets discovery, the half-month in the year denoted by a letter A through Y (with I omitted to avoid confusion), and a number signifying the order in which the comet was found within that half-month. Thus, Halleys Comet is designated 1P/1682 Q1 when Halley saw it in August 1682, but 1P/1982 U1 when it was first spotted by astronomers before its predicted perihelion (point when closest to the Sun) passage in 1986. This identification system is similar to that now used for asteroid discoveries, though the asteroids are so designated only when they are first discovered. (The asteroids are later given official catalog numbers and names.) Formerly, a number after the name of a periodic comet denoted its order among comets discovered by that individual or group, but for new comets there would be no such distinguishing number.

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Comet | Definition, Composition, & Facts | Britannica

How to Watch the Green Comet During the New Moon – The New York Times

A green-hued comet from the outer solar system is set to swing through Earths neighborhood in the coming days for the first time in 50,000 years.

The comet has been steadily gaining brightness and will make its closest approach on Feb. 2, when it comes within 26.4 million miles of the planet 110 times the distance to the moon. From the Northern Hemisphere, the comet is likely to be faintly visible to the naked eye.

But you dont have to wait until February to spot this visitor. The coming weekend may offer favorable viewing opportunities with a pair of binoculars when the new moon creates darker skies.

The comet is known as C/2022 E3 (Z.T.F.) because astronomers discovered it in March 2022 using a telescope on Palomar Mountain in California called the Zwicky Transient Facility (or Z.T.F.).

At the time, the cosmic interloper was just inside the orbit of Jupiter and roughly 25,000 times dimmer than the faintest star visible to the naked eye. But Z.T.F., with a camera that has a wide field of view, scans the entire visible sky each night and is well-suited to discover such objects.

Comets are clumps of dust and frozen gases, sometimes described by astronomers as dirty snowballs. Most are believed to originate from the distant, icy reaches of the solar system where gravitational agitations sometimes push them toward the sun an interaction that transforms them into gorgeous cosmic objects.

When they leave their deep freeze, the heat from the sun erodes their surfaces, and they start spewing gases and dust until they host a glowing core, known as the coma, and a flamelike tail that can stretch for millions of miles.

Theyre alive, Laurence ORourke, an astronomer with the European Space Agency, said. When theyre far from the sun, theyre sleeping, and when they get close to the sun, they wake up.

C/2022 E3 (Z.T.F.), for example, is now glowing green because ultraviolet radiation from the sun is absorbed by a molecule in the comet called diatomic carbon that is, two carbon atoms fused together. The reaction emits green light.

The brightness of comets can be unpredictable. When scientists first discovered the object last year, they knew only that it had potential to be visible from Earth.

Because each comet is its own living being, you dont know how its going to react until it passes the sun, Dr. ORourke said.

Comet C/2022 E3 (Z.T.F.) made its closest approach to the sun on Jan. 12, and the comet is now steadily brightening as it swings toward the Earth. While the comet wont pass us until Feb. 2, it is already nearly visible to the naked eye an encouraging sign for viewing opportunities, said Mike Kelley, an astronomer at the University of Maryland and the co-lead of the solar system working group at the Zwicky Transient Facility.

Still, seeing the comet could require dark skies and an experienced observer, Dr. Kelly said.

In addition, comets can always surprise us. Sometimes there can be a big explosion of gas and dust, and the comet might get suddenly brighter even after it has left the sun behind.

To catch the comet, look north.

On Jan. 21, the night of the new moon and thus the darkest skies, the comet will be close to Draco the dragon-shaped constellation that runs between the Big Dipper and the Little Dipper.

Over the following nights, the comet will creep along the dragons tail. And on Jan. 30, the comet will reside directly between the Big Dippers cup and Polaris, the North Star. If youre accustomed to finding the North Star by following the two stars on the end of the Big Dippers cup, then you should be able to spot the comet. Simply scan that imaginary line until you see a faint smudge.

If youre struggling, the comet might still be too faint or there might be too much light pollution. Try with a pair of binoculars.

Even with relatively modest binoculars, the powdery, fuzzy or smoky character of the star ought to make it clear its a comet, said E. C. Krupp, the director at Griffith Observatory in Los Angeles.

A telescope will help you spot the colors and finer details, including the comets glowing coma and lengthy tail.

For anyone living above the 35th parallel imagine a curving East-West line running from North Carolina through the Texas Panhandle out to Southern California the comet will be visible all night starting Jan. 22. But it is relatively low on the horizon in the early evening, and it might be better to look for the comet later in the evening or even early in the morning when the comet swings higher in the sky.

Dr. Krupp recommends looking this weekend when the phase of the moon is new, and it therefore wont cast a glow over the sky. But the comet will become brighter as it gets closer to Earth and will be easier to spot toward the end of the month. If you wait until then, you might want to try early in the morning after the moon has set.

Either way, the hunt will be fun.

Its sort of like searching for some endangered species, and then it pops into view, Dr. Krupp said. That really is a charmer of an experience.

Comets are relics of the early solar system and may have been responsible for seeding early Earth with the building blocks for life.

It really is a situation where we most likely would not exist without their existence, Dr. ORourke said.

And yet we dont get many opportunities to study these objects, given that only a few each year are bright enough to be seen with the naked eye. As such, cometary astronomers across the globe will observe C/2022 E3 (Z.T.F.) over the coming months.

Were looking for our solar systems place in the universe, said Dr. Kelley, who will use the James Webb Space Telescope to observe the comet at the end of February. He wants to better understand how our planet formed in order to note the conditions that gave rise to life on Earth.

But Dr. Kelley and others have to work quickly. After a brief appearance in the night sky, its unclear where C/2022 E3 (Z.T.F.) may go. Because these objects are so loosely bound to our solar system, the suns gravitational influence might force the comet to take another trip around our star perhaps not returning for another 50,000 years. Or the sun might fling the comet from the solar system entirely.

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How to Watch the Green Comet During the New Moon - The New York Times

How to view and photograph comets | Space

Comets are notoriously fickle things. Some are given high expectations of putting on a good show and fail to deliver. In contrast, others, originally thought to be unremarkable, may suddenly flare up to glow at a magnitude that's visible to the unaided eye. In general, it's quite difficult to say just how a comet will behave.

In this guide, we'll be highlighting the latest naked eye comet passing by Earth and give you plenty of tips on how to observe and photograph this and many other types of comets. We'll be covering the best viewing locations, exploring ideal viewing situations and making concrete suggestions to specific telescopes and binoculars that will aid skywatchers as they observe the comet, as well as outlining the history of each comet and where it's come from.

Below we've also laid out a fool-proof guide on how to photograph a comet with tips on which camera, lens and photography accessories to choose from, with additional advice on composition, camera settings and other techniques required to photograph comets.

The question is, can you see comet C/2022 E3 (ZTF) with the naked eye? By perigee (the point in an orbit at which it is closest to Earth) it is hoped that C/2022 E3 (ZTF) will be brighter than magnitude +6.0, making it visible to the naked eye, at least from very dark sites. As previously mentioned, how much brighter than magnitude +6.0 will remain unknown comets can be notoriously unpredictable.

In mid-January, the comet rises in the northeast around midnight local time and is best viewed higher in the sky before dawn, while it is still dark. As the month progresses, C/2022 E3 (ZTF) rises earlier and earlier at perigee, your best bet is to look for it around 10 pm local time. The Pole Star, Polaris, will be a good guide, since the comet is 11.5 degrees to the northeast of it on 31 January.

Currently, C/2022 E3 (ZTF) is just above magnitude +7.0. This means it is too faint to be seen with the unaided eye; you'll need 7x50 or 10x50 binoculars for comfortable viewing or a small telescope, around 4-inches (100mm) in aperture in order to spot it as a greenish, fuzzy smudge of light. You can check out our best telescopes or best binoculars guides for some great models to suit a variety of budgets. Although sometimes comets have long tails, C/2022 E3 (ZTF) doesn't have a very long tail, at least not yet.

Best telescopes for viewing comets

If the comet does brighten near perigee, as is hoped, it could reach magnitude +5.0. Technically this is within visibility of the unaided human eye, but it is still very faint if you live near a town with light pollution, you probably won't be able to see the comet, so it is recommended that you head to a dark site out of your town to have the best chance of seeing it. Of course, it might not get this bright, or it might have an outburst and be even brighter than expected. We'll just have to wait and see.

Best binoculars for viewing comets

Since the naked-eye view is unlikely to wow you, then for the best scenes, imaging is the way to go. However, to get a good image you'll need some very particular instruments.

There are two main ways to photograph comets successfully: with a DSLR or mirrorless camera, a camera lens and a tripod; or a camera/smartphone hooked up to a telescope.

The best camera to photograph a comet is, unsurprisingly, one of the best cameras for astrophotography. This calls for good sensitivity to light by utilizing a high ISO range, the ability to keep noise to a minimum and a large image sensor (ideally 35mm full-frame or larger) for lower image noise and a propensity toward a wider dynamic range. See our two top suggestions below, and take a look at our best cameras for astrophotography guide if you want to shop around.

Best mirrorless for photographing comets

There are several types of camera lenses that are suitable for comet photography, and which one you end up using depends mostly on the brand of your camera system. However, on the whole you want to look for a lens that has a fast maximum aperture (f/2.8 or narrower) and has minimal chromatic aberration (color fringing) and optical distortion. See two suggestions below that sit in our best lenses for astrophotography and best zoom lenses guides.

Best lenses for photographing comets

But for the best images, you'll need either a DSLR/mirrorless camera or a dedicated CCD or CMOS camera attached to a long-focal-length telescope, all on a sturdy mount that isn't going to shake and is controlled by a laptop or tablet.

For comet photography through a telescope, we would recommend at least 4-inches (100mm) aperture, a 1.25-inch eyepiece kit (as they fit the majority of telescopes) or binoculars that have large objective lenses with good magnification like 7x50 up to 20x80. See below for our specific recommendations on the latest and best telescopes, binoculars and accessories that will help you view comets.

Astronomy gear to view comets

There is a bagful of camera accessories astrophotographers can buy that will make comet photography easier. However, the key items to get in order to take better, more accurate astrophotos of comets are as follows.

A good tripod is one that will keep the camera and lens stable even during strong winds. Long exposures are required when photographing comets because they are normally best viewed at night because they are quite dim. If the camera moves during exposure then the entire photograph will become blurred, so one of the best tripods for astrophotography will keep the camera stationary when shooting. Pay attention to the maximum payload of each tripod though, the max payload can be calculated by adding the weight of your camera (with memory cards and battery inserted) and your lens, plus any accessories like lens warmers or star trackers. If the weight of all the gear you'll be using exceeds the tripod's maximum payload the tripod may be unstable and it is unlikely you will get sharp photographs of comets.

Star trackers are mounts that move with earth's rotation in order to allow longer exposures (or multiple long exposures over several minutes or hours) of celestial objects. While they are designed for tracking stars they may be helpful in keeping the frame steady when shooting comets, especially on long focal length telephoto lenses.

It's important not to knock the camera or lens during long exposures so as to avoid camera shake blur. That's why a remote shutter release should be used when photographing comets and all astrophotography subjects. They come in a variety of shapes and sizes, with wires that attach to proprietary ports on cameras but also in wireless models. We would recommend wireless models on the whole because it avoids the inevitable tangling on wires when shooting, but wired options are usually less expensive.

There aren't many filters that are useful for comet photography. Neutral density filters make the scene darker so would actually hinder rather than help, and graduated neutral density filters are usually used to darken a bright sky which isn't a problem at night.

However, light pollution filters may prove beneficial to those that are forced to shoot comets near towns and cities with street lighting. The best light pollution filters help alleviate the orange glow found in astrophotos taken near light-polluted areas. Many photographers prefer to edit light pollution out in post-processing software such as Adobe Lightroom or Adobe Photoshop, but for those that want a running start or who prefer to avoid image editing altogether, light pollution filters are a safe bet.

Shooting locations vary wildly and depend on the trajectory of a comet as it travels through space and past earth. Keep an eye at the top of this page, and on our other news stories to see where the latest comet is visible in skies near you. There are, however, some key tips on the best comet shooting locations.

The best location for photographing a comet is one that is dark and free from light pollution. Avoid cities and busy towns that have a lot of street lighting as light pollution will glow in the night sky. Instead, use a website like Dark Site Finder to find dark sky locations nearby and schedule a visit.

Cloudless nights are best so use a weather app or check the local forecast before heading out. In the northern hemisphere, the winter months give longer nights which offers greater opportunity for shooting comets and astrophotographs but this often comes with colder temperatures and inclement weather so dress appropriately.

Capturing the comet hanging in the sky on its own is fine for recording purposes, but to make a truly captivating image it may be worth pre-planning a shoot in order to include interesting foreground features. A simple landscape in the foreground adds context but seeking out local landmarks and interesting land features will help push your comet photographs to the next level. Waterfalls, ruins, rock formations or even distant tall buildings (provided there isn't too much light pollution) can all improve a comet photograph.

Comet C/2021 A1 a.k.a.Comet Leonard (opens in new tab) is on a last dash through our solar system before disappearing a little later in 2022. The comet has been a dazzling sight in binoculars or telescopes, appearing with a twisted tail and if you have a great camera, a green coma.

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How to view and photograph comets | Space



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