Daily Archives: December 24, 2019

It's been an interesting year for astronomy news.

I could start every year-end article with that line. The sheer number of telescopes and spacecraft poking and prodding the Universe practically guarantees that we'll see a few breakthroughs or at least significant jumps every few months in one field or another.

As I went through the articles I've written and the press releases I've received these past 12 months, it wasn't too hard to find the brain-grabbing headlines, as you'll see below. But I was also struck by how much solid progress is being made in astronomy (and other sciences of course) that weren't big banner stories. Some were about incremental but important discoveries, some about missions that ended, and some that were just interesting and worth reading about.

Because of that, this isn't really a Top Five list. It's more of a "here are a lot of cool stories, and five of them I'll bring special attention to, but hey you should look at a bunch of others as well!"

As for the five, three of them are close to home, one of them is close to home but hearkens to distant unknown realms, and the fifth is about as not close to home as you can get, metaphorically at least.

OSIRIS-REx is a NASA mission that arrived at the 500-meter-wide asteroid Bennu on the last day of 2018. The goal of the mission, among other things, is to survey the surface, do mineralogical studies, and grab some samples that it will eventually return to Earth. The overall goal is to understand asteroids better, what they're made of, their structure, what their environment is like.

Bennu is not a solid monolithic rock, but is instead a rubble pile, a big collection of rocks held together by their own meager gravity. We knew these existed, but we knew very little of their behavior up close. And that's why it was a pretty dang big shock to find out that Bennu is active: It's spitting small rocks into space!

This was unexpected, to say the least. But the images make it pretty clear: Rocks up to 10 centimeters in size were being shot out into space at speeds of up to 3 meters per second! Given that Bennu's surface gravity is something like 1/100,000th of Earth's, that's an appreciable velocity. Some of these bits orbited the asteroid and fell back, but others escaped entirely.

A paper just published posits three mechanisms that might cause this: rocks fracturing due to thermal stress between the hot days and frigid nights on the asteroid's surface, water outgassing from phyllosilicates (clays) in the rocks applying pressure to smaller bits and ejecting them, and micrometeorite impacts dislodging material and blasting them away. It's not clear which of these three is the culprit, or if they're working in some combination.

Asteroids, it turns out, are pretty surprising in many ways; they're certainly not just dead rocks floating around the Sun. Perhaps OSIRIS-REx will get more info on this weird behavior, since it'll be hanging around Bennu until March 2020. Hopefully it'll find other strange stuff, too.

Noteworthy related articles: The Japanese spacecraft Hayabusa2 has left its own target asteroid Ryugu behind, and is heading back to Earth (arriving in 2023) with samples. It got them by firing a cannon at the surface, and also dropped four rovers down to land on the asteroid as well.

On 17 January, 2019, the Moon slipped into the shadow Earth casts into space, creating a total lunar eclipse.

While beautiful, these events are relatively common, and of limited scientific potential. But this one threw a monkey into the wrench: While millions of people watched the event either outside for themselves or in the many livestreams, a small asteroid slammed into the shadowed lunar surface, creating a fireball easily visible in small telescopes!

It was later determined that the interplanetary debris was a 45-kilogram rock roughly the size of a beach ball, and it hit the Moon at a speed of about 61,000 kilometers per hour. The resulting release of energy was equivalent to the detonation of about 1.5 tons of TNT, carving out a crater something like 1015 meters wide. Oof.

Impacts happen on the Moon pretty often, but they're not usually this well characterized; it helped a lot that so many telescopes were trained on the Moon at the time, so that high-quality video could be analyzed. It also happened in the darkest area of the eclipsed surface, so the contrast was high.

My own connection to this impact is that I was out in my driveway doing a live feed on Periscope with my cell phone attached to a small spotting telescope. I was having a hard time keeping the 'scope aimed and the phonecam focused, and I was adjusting the setup right when the impact occurred. I missed seeing it by seconds!

Lesson learned. Next time I'll do more prep and use my big scope, which is easier to control and track. But I'm honestly really glad so many people got to see such a rare and cool event.

Noteworthy related articles: A meteorite hit a house in Uruguay, and the comet 42/P Wirtanen was impacted by some debris that caused it to outburst. Also, getting to the Moon isn't easy; India lost a lander, as did Israel, though China landed a rover on the far side which was seen by LRO from orbit.

The New Horizons spacecraft zipped by Pluto in July 2015, returning amazing detailed images and data of the tiny, icy world. But this was a flyby, and New Horizons continued on into the dark after the encounter.

Projecting its path into the future, astronomers looked for more potential targets for the spacecraft, and discovered 2014 MU69, what's called a Kuiper Belt Object, an icy rock that orbits the Sun past Neptune. The mission was given the green light, and it fired its engine to set course for its frigid destination.

The flyby was on 1 January 2019 (so it counts for this list!), and due to the distance 6.6 billion kilometers from Earth the data transmission rate was low, so we had to wait almost two months to get the high-res images. But it was so worth that wait.

This is a mosaic taken from a distance of about 6,600 km, when the spacecraft was still 6 minutes from closest approach. The shape wasn't unexpected; previous observations had indicated it was double-lobed or possibly binary. MU69 now officially named Arrokoth looks like a contact binary, with two separate objects touching at a single neck region. Weirdly, it looks like the two lobes are actually very flat, which is surprising.

New Horizons is still out there, moving away from the Sun. It's possible it may visit another KBO, but its power source is good for another decade or two, so it will measure the environment of the outer solar system and provide scientists with data for some time to come.

Noteworthy related articles: Where do the big moons of KBOs come from? and a new idea about how one of Neptune's small weird moons formed.

In 2017, astronomers discovered an object moving so rapidly through our solar system that it must have come from another star. Called Oumuamua, it was the first confirmed interstellar visitor ever seen. The question naturally arose: How often do these things pass through?

In late 2019 we got another clue: A second object was discovered, also moving so rapidly there was no way it could've come from our own solar system. Another alien visitor was confirmed.

Named 2I/Borisov (the second interstellar object ever seen, discovered by amateur astronomer Gennadiy Borisov), it was immediately pounced upon by observatories across our planet (and above it). Unlike 'Oumuamua, which was discovered after it had passed the Sun and Earth and was on its way out, 2I/Borisov was discovered while still on its way in, which was critical: For one thing it gave astronomers more time to study it, and for another we could watch it approach the Sun, warm up, and become active.

Sure enough, it was seen to have a gaseous head around it, and a tail, too. As I've written many times before, the weirdest thing about 2I/Borisov is just how ordinary it is. Except for its exceptional speed, it looks exactly like any run of the mill solar system comet! 'Oumuamua was pretty weird; it appears to very elongated, and no outgassing was directly seen from it. It's unclear why 'Oumuamua is so odd.

But 2I/Borisov? It has the same molecules and elements in it as solar system comets, and it behaves in the exact way you'd expect our local artisanal comets do. Remember, this comet formed around another star! Something happened to eject it from its home (maybe a close encounter with a giant planet) and send it into deep space, traveling who knows how many light years hundreds of trillions of kilometers, certainly before zipping past us. Yet for all that, it looks like a twin of any comet of our own.

I love this! It shows us that the basic ingredients, the basic conditions, of environments around other stars are much like they are here. If, like me, you wonder if other Earths dot the sky, if there may be other beings out there looking up in curiosity and awe, then the mundanity if this object is the most exciting thing about it.

2I/Borisov has already passed its closest point to the Sun, and will be nearest Earth late in December (though still nearly 300 million km away). It'll be months before it's too far away to see, so there will be many, many more observations of it to come. And the other lesson here is that it's only a matter of time before we spot more voyagers like it. What will we learn from them?

Noteworthy related articles: Could the weird behavior of Boyajian's Star be due to an evaporating exomoon? and exocomets are raining down on Beta Pictoris.

Nothing in astronomy captures people's attention and wonder like a black hole. Capable of utter destruction yet the engines of the formation of stars in galaxies as well, everything about them is fascinating and weird.

Yet for all the articles written about them, all the observations made of them, all the theoretical calculations made about them, we still have never actually seen one. And you can't. There's a reason we call them black holes.

But we can see their impact on the environment around them. Some are actively feeding, matter piling up in huge disks around them before falling over the cliff of infinity, and that material is extremely hot, glowing across the electromagnetic spectrum. The problem is that even though these disks can be light years across, they're so far away from Earth that distance shrinks them to irresolution.

until now. Over the course of four nights in 2017, an array of seven telescopes across the planet were aimed at the heart of M87, a galaxy 55 million light years away in the constellation of Virgo. It's the nearest active galaxy, one with a supermassive black hole equal to 6.5 billion times the Sun's mass, and one that is accreting vast amounts of material. The observations were so difficult and complex it took nearly two years to process them, but when the results were released in April 2019, people across the planet gave out a collective gasp:

That picture is amazing. It's the actual image of material circling the black hole some few dozen billion kilometers out and of course there's that gaping dark hole in the center. That's not the black hole itself! It's where material orbiting the black hole is so close that the light from it can actually orbit the hole a few times before falling in. That region is called the photon sphere, and is about 2.5 times bigger than the event horizon (the point of no return for anything getting too close to a black hole; for M87 the event horizon is about 40 billion kilometers across, roughly eight times the distance of Neptune from the Sun). This area is sometimes called the shadow of the black hole, but I prefer to think of it as the silhouette. Either way, it's just an analogy. But it's where light cannot get out, so it looks like a donut hole.

The image closely matches what we expected to see from a close-up image of a black hole. And it's only the first of its kind: The Event Horizon Telescope, as the array is collectively called, will be aimed at more soon, including Sgr A*, the supermassive black hole in our own galaxy. At just 26,000 light years away it's much closer, but far less massive and therefore smaller; coincidentally the two black holes appear to be about the same apparent size our sky. I can't wait to see that one!

And with this new powerful technology, we'll be seeing a lot more from this array. We've known about black holes for a long time, but there's still a lot about them we don't understand. This image, and the ones that will no doubt follow, will help us wrap our heads around these objects that literally wrap space and time around them.

Noteworthy related articles: Our local supermassive black hole erupted and we don't know why, it also ejected a star right our of the galaxy, and how astronomers measured the staggering 2.3 billion solar mass black hole in a galaxy 100 million light years away.

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The top 5 astronomy stories for 2019 - SYFY WIRE

While the mission Aditya of the Indian Space Research Organisation (ISRO) will play a crucial role towards ensuring safety of satellites, the 3.6 metre optical telescope at Aryabhatta Research Institute of Observational Sciences (ARIES), Devsthal will be the future of astronomy in India. Stating this, the recently appointed director of the institute professor Deepankar Banerjee further informed that ARIES is also participating in the construction of the worlds biggest 30 metre telescope.

Banerjee said that ISRO will launch mission Aditya within the next two years. He said that this mission can not really be compared to NASAs Parker solar probe. However, the Indian mission will prove to be a milestone for the protection of satellites from the powerful solar particles which affect satellites. He said that information will be relayed by the Aditya probe about the highly charged solar particles on their emission.

This will not only help in protection of satellites from such particles but also help address the hindrances created by solar storms in operation of aircraft flights. The mission was slated to be launched in 2013 but was delayed due to factors related to high level equipment and development of high level technology.

He further informed that ARIES will be playing the lead role in the TMT project involving five nations. With the institute working at a brisk pace for this, the results will be visible soon. Regarding the institutes 3.6 metre telescope, he said that about a dozen research papers based on work through this telescope have been published so far.

This shows that this telescope will play a major role in astronomy in the future. However, for this, various new equipment have to be incorporated into the telescope. Work to facilitate this is being undertaken at a swift pace, he added. Meanwhile, institute officials said that a visitor centre will also be established at ARIES soon. The plan for this will be finalised soon. Establishment of the visitor centre will enable the visitors and local youngsters to gain knowledge related to astronomy. It will also help in boosting the interest of the youth the sphere of astrology.

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ARIES to play bigger role in astronomy - Daily Pioneer

According to the new data, the Milky Way was once what astronomers call a starburst galaxy. Its an area commonly seen in other parts of the universe where stars form at a fast rate. About 80 percent of the stars in the center of the Milky Way were formed between 8 billion and 13.5 billion years ago. But about 1 billion years ago, another intense star-formation burst happened, creating many massive new stars. These large stars live shorter lives than small stars. And when large stars die, they explode. So the starburst led to a surge in supernovae and a dramatic period of star formation all at around the same time.

This burst of activity, which must have resulted in the explosion of more than 100,000 supernovae, was probably one of the most energetic events in the whole history of the Milky Way, said researcher Francisco Nogueras-Lara in a press release.

The new data also throw out the old theory that all stars were formed at around the same time.

The study was published in Nature Astronomy.

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When the Milky Way erupted in 100000 supernovae - Astronomy Magazine

Dean Regas, Special to Cincinnati Enquirer Published 11:53 a.m. ET Dec. 23, 2019 | Updated 12:02 p.m. ET Dec. 23, 2019

The planet Venus, left, and the crescent moon form a striking pair in the sky.(Photo: AP file)

In 2019, astronomers captured the first picture of a black hole, the world celebrated the 50th anniversary of the moon landingand Mercury crossed in front of the sun for the last time until 2032.What out-of-this-world occurrences will be happening in the universe next year?Here are the cant-miss astronomical events of 2020.

Maybe youve seen it already: the planet Venus is blazing in the southwestern sky just after dark.Venus shines brighter than any other star and may even make you think a UFO is about to land its that suspiciously bright.

Venus will be visible just after sunset every night until May and the best nights to catch this planet are when the crescent moon stands nearby.These Venus-moon conjunctions will occur on the evenings of Jan.27 and 28, Feb.27, March 27 and 28, April 26, and finish up on May 23 and 24.No telescope needed: These picturesque pairings of the Moon and Venus amid the afterglow of sunset are best observed with the naked eye.

Pluto as seen by the New Horizons spacecraft, which carried a small portion of the ashes of discoverer Clyde Tombaugh.(Photo: Associated Press)

On Feb.18, 1930, American astronomer Clyde Tombaugh made a momentous discovery.By comparing two pictures taken at different times, he saw a tiny dot move through space.That was Pluto, and Tombaughs discovery turns 90 this year.Pluto was considered a planet until 2006 when it was infamously demoted to dwarf planet status, but in 2015, the unmanned New Horizons spacecraft flew by this tiny, icy world and gave Pluto fans close up images from the far reaches of the solar system.

Fun fact: The average temperature on Mars is minus 81-degrees Fahrenheit, according to NASA. The average temperature on earth is 57-degrees.(Photo: Andrei Lacatusu)

The Red Planet is back in 2020.Mars, always a crowd favorite, returns to the evening sky in the fall when it will appear as a bright, orange beacon in the night sky.The night of closest approach will be Oct.6, but you will have plenty of time to get to know Mars. It will shine brightly every night from September 2020 to early 2021.

There will be a full moon on Halloween night in 2020.(Photo: The Enquirer/Michael E. Keating)

Perhaps the biggest astronomical story of 2020 will occur on Halloween night.Not only is Oct.31 a Saturday this year, but it will also be the night of a full moon.But wait, theres more. Since this will be the second full moon of October (there will be one on Oct. 1), it will also be considered a Blue Moon.The moon wont actually turn blue, but for backyard stargazers and trick-or-treaters this will make a great backdrop to the holiday and is sure to fuel internet superstitions.

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There will be a whopping four lunar eclipses and two solar eclipses in 2020, but none of them are good for viewers in the United States or Canada.The lunar eclipses on Jan.10, June 5, July 5and Nov.30 are all penumbral eclipses, meaning the moon enters a fainter shadow of the Earth and is not noticeable to the average viewer.The solar eclipse on June 21 is only visible from the Eastern Hemisphere and the total solar eclipse on Dec.14 is only visible from Chile and Argentina.So plan some trips and chase eclipses all year long.

Head to Cincinnati Observatory in 2020 for a new look at the night.(Photo: Leigh Taylor, Enquirer/Leigh Taylor)

The two largest planets in the solar system, Jupiter and Saturn will be visible all summer and fall of 2020.Although they are hundreds of millions of miles apart, each night, they will appear closer together in our skies. The best alignment will be on Dec.21, when Jupiter and Saturn will seem so close together in the sky that they will almost touch. This Jupiter-Saturn conjunction only happens every 20 years, but this is an exceptionally close pairing. If you aim a telescope at them that evening, it may be the only time in your life where you can see the surface of Jupiter and the rings of Saturn at the same time.

Heres hoping for a lot of clear skies in 2020 so you dont miss even one exciting event in the sky.

Dean Regas is the Astronomer for the Cincinnati Observatory, and author of the books 100 Things to See in the Night Sky and Facts from Space! He can be reached at dean@cincinnatiobservatory.org

Where: Cincinnati Observatory

What: Three-night astronomy course. Perfect for beginners who want to learn more about observing the night sky.

When: Tuesday, Jan.7, 14, and 21, from 7-9 p.m.

Admission: $50 per person for the series, $40 per Observatory member

Information: Reservations required by calling 513-321-5186 or online at http://www.cincinnatiobservatory.org.

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Keep your eye on the sky: Astronomical highlights of 2020 - The Cincinnati Enquirer

In the course of conducting solar astronomy, scientists have noticed that periodically, the Suns tangled magnetic field lines will snap and then realign. This process is known as magnetic reconnection, where the magnetic topology of a body is rearranged and magnetic energy is converted into kinetic energy, thermal energy, and particle acceleration.

However, while observing the Sun, a team of Indian astronomers recently witnessed something unprecedented a magnetic reconnection that was triggered by a nearby eruption. This observation has confirmed a decade-old theory about magnetic reconnections and external drivers, and could also lead to a revolution in our understanding of space weather and controlled fusion and plasma experiments.

The team responsible for the discovery was led by Abhishek Srivastava, a solar scientist from the Indian Institute of Technology (BHU), and included astronomers from the University of South Bohemia, the School of Earth and Space Sciences at Peking University, Centre for mathematical Plasma Astrophysics, the Indian Institute of Astrophysics, and the Armagh Observatory.

Using data from NASAs Solar Dynamics Observatory, Srivastava and his colleagues observed a magnetic explosion unlike any other. It began in the upper reaches of the Suns atmosphere (the corona), where a large loop of material (aka. a prominence) was launched by an eruption from the Suns surface. This loop then began descending back to the surface, but then ran into a mass of entangled field lines, triggering a magnetic explosion.

As Abhishek Srivastava, a solar scientist from the Indian Institute of Technology (BHU), explained:

This was the first observation of an external driver of magnetic reconnection. This could be very useful for understanding other systems. For example, Earths and planetary magnetospheres, other magnetized plasma sources, including experiments at laboratory scales where plasma is highly diffusive and very hard to control.

In previous cases, magnetic reconnections that were observed on both the Sun and around Earth had been spontaneous in nature. These occur only when conditions are just right in a particular region of the Sun, which includes a thin sheet of ionized gas (aka. plasma) that only conducts electric current but only weakly.

While the possibility of forced reconnections driven by explosions was first theorized 15 years ago, none had ever been seen directly. This type of reconnection can happen in a wider range of places where plasma sheets have even lower resistance to conducting electric current. However, it also requires an eruption to trigger it, which will squeeze the plasma and magnetic fields and cause them to reconnect.

Using the SDO, the team was able to study this plasma by examining the Sun at a wavelength that showed particles heated to between 1 2 million C (1.8 3.6 million F). This allowed them to observe and take images of a forced reconnection event in the solar corona for the first time in history. It began with the prominence in the corona falling back into the photosphere, where it ran into a mess of field lines and reconnected in a distinctive X-shape.

Magnetic reconnections offer a possible explanation for why the Suns corona is actually millions of degrees hotter than the lower atmosphere which has been an enduring mystery for astronomers. To address this, solar scientists have spent decades looking for a possible mechanism that could be responsible for driving this heat.

With this in mind, Srivastava and his team observed the plasma in multiple ultraviolet wavelengths to calculate its temperature after the reconnection event. The data showed that the prominence, which was cooler than the surrounding corona, became hotter after the reconnection event. This suggests that forced reconnection could be responsible for heating the corona locally.

While spontaneous reconnection could still be a contributing factor, forced reconnections appear to be a bigger one, capable of raising plasma temperatures faster, higher, and in a more controlled fashion. In the meantime, Srivastava and his colleagues will continue to look for more forced reconnection events in the hopes of better understanding the mechanics behind them and how often they might happen.

These results could also lead to additional solar research to see if eruption events like flares and coronal mass ejections could also cause forced reconnection. Since these eruptions are the driving force behind space weather, which can wreak havoc on satellites and electronic infrastructure here on Earth, further research into forced reconnection could help lead to better predictive models

These, in turn, would allow for early warnings and preemptive measures to be taken in the event of a flare or ejection. Understanding how magnetic reconnection can be forced by an external driver could also lead to breakthroughs in the lab. This is particularly true of fusion experiments, where scientists are working to figure out how to control streams of super-heated plasma.

Credit: NASA, The Astrophysical Journal

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Astronomers Discovered a New Kind of Explosion That the Sun Can Do - Universe Today

Any number of scientific discoveries or events make the "best of" lists every year. Well, our astronomy contributor Jean Creighton is no different, and she shares her picks for 2019:

Lake Effect's Bonnie North speaks with astronomy contributor Jean Creighton.

First all-female spacewalk

The first all-female spacewalk took place on Oct. 18. Astronauts Christina Koch and Jessica Meir made the historic excursion.

The initial all-female spacewalk was planned in March, but it was canceled.

"What's interesting here is that the reason why the original crew didn't get to do it was because they didn't have a suit that was suitable for two women at the same time," Creighton explains.

As NASA makes new missions to the Moon and possibly even Mars, she says spacesuits will need to be made individually for each astronaut.

"Because people are going to be spending a lot of time in space, they're going to have suits that will be made to their particular size men or women," she says.

First molecule in the universe

Now, we go from a huge spacewalk to something that's very, very, very small. After decades of searching, scientists discovered the first molecule that formed in the universe. Keep in mind, the universe is almost 14 billion years old.

Scientists believe the universe's first type of molecule is helium hydride. It's a combination of helium and hydrogen, according to NASA, and likely formed 100,000 years after the Big Bang.

"That was made in the lab in 1925, almost 100 years ago. But it was elusive. We couldn't identify it in any of the astronomical objects that we've been looking at," Creighton says.

But finally, a NASA aircraft called SOFIA (Stratospheric Observatory for Infrared Astronomy) made it possible for scientists to see helium hydride for the first time.

First photograph of a supermassive black hole

"We have been lucky in the black hole department for the last few years. This year, it was a direct image of a supermassive black hole at the center of very cool galaxy, which is called M87," says Creighton.

She says what's cool about M87 is that way before the photograph, scientists were able to see "huge lobes." Since the lobes were much larger than the galaxy, scientists were curious about how the lobes were powered.

"It turns out, at the core, as we now understand of most galaxies, of M87 there is a supermassive black hole that as it spins, it ejects sharp jets that pile into the gas and make these balloons of gas at the intersection of where the jet hits and where clouds of material might be," she explains.

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What Cool Things Happened In Astronomy In 2019 - WUWM

When stars exhaust their supply of fuel, they collapse under their own weight and explode, blowing off their outer layers in an event known as a supernova. In some cases, these events leave behind neutron stars, the smallest and densest of stellar objects (with the exception of certain theoretical stars) that sometimes spin rapidly. Pulsars, a class of neutron star, can spin up to several hundred times per second.

One such object, designated J0030+0451 (J0030), is located about 1,100 light-years from Earth in the Pisces constellation. Recently, scientists using NASAs Neutron star Interior Composition Explorer (NICER) were able to measure the pulsars size and mass. In the process, they also managed to locate the various hot spots on its surface, effectively creating the first map of a neutron star.

Since 2017, NICER has been conducting observations from the International Space Station (ISS) for the purpose of creating of learning what goes on inside a neutron star. In addition to providing high-precision measurements of neutron stars and other super-dense objects, the data it collects will also be used to create an X-ray map of the cosmos and to test pulsars as a possible navigation beacon.

As Paul Hertz, the director of NASAs astrophysics division, said in a recent NASA press release:

From its perch on the space station, NICER is revolutionizing our understanding of pulsars. Pulsars were discovered more than 50 years ago as beacons of stars that have collapsed into dense cores, behaving unlike anything we see on Earth. With NICER we can probe the nature of these dense remnants in ways that seemed impossible until now.

For decades, scientists have been studying pulsars in the hopes of getting a better understanding of their inner workings. According to the simplest model, pulsars have incredibly powerful magnetic fields shaped like a dipole magnet. Combined with the pulsars rotation, this causes particles from its surface to be focused into tight beams emitted from the poles. This creates a strong strobing effect that resembles a lighthouse to observers.

This effect leads to variations in the pulsars brightness (in the X-ray wavelength), which astronomers have observed in the past. At the same time, astronomers have also observed hotspots on the surface of pulsars, which are the result of their magnetic fields ripping particles from the surface and accreting them around the poles. While the entire surface glows brightly in X-rays, these hot spots glow brighter.

However, the new NICER studies of J0030 (a millisecond pulsar that revolves 205 times per second) showed that pulsars arent that simple. Using NICER data obtained from July 2017 to December 2018, two groups of scientists mapped out the hotspots on J0030 and came to similar conclusions about its mass and size.

The first team was led by Thomas Riley and his supervisor Anna Watts, a doctoral student in computational astrophysics and a professor of astrophysics (respectively) at the University of Amsterdam. To recreate the X-ray signals they observed, Riley and his colleagues conducted simulations of overlapping circles of different sizes and temperatures using the Dutch national supercomputer Cartesius.

In addition to determining that J0030 is around 1.3 Solar masses and 25.4 km (15.8 mi) wide, they identified two hot spots one small and circular, the other long and crescent-shaped. The second team, led by astronomy professor Cole Miller of the University of Maryland, conducted similar simulations using UMDs Deepthought2 supercomputer.

They found that J0030 is 1.4 Solar masses, measures 26 km (16.2 mi) wide, and came up with two solutions for hotspots. In the first, they identified two possible hotspots, one of which has two ovals that closely matches the results of Rileys team. In the second, they found a possible third hotspot located around the pulsars southern rotational pole.

As Riley explained, these results revealed a great deal about J0030 and other pulsars:

When we first started working on J0030, our understanding of how to simulate pulsars was incomplete, and it still is. But thanks to NICERs detailed data, open-source tools, high-performance computers and great teamwork, we now have a framework for developing more realistic models of these objects.

As predicted by Einsteins General Theory of Relativity, a pulsar is so dense that its gravity warps the very fabric of space-time around it. The effect is so pronounced that light coming from the side facing away from the observer is bent and redirected towards them. This makes the star look bigger than it really is and means that hot spots dont disappear entirely when they rotate away from the observer.

Thanks to NICERs precision, which is about 20 times that of previous instruments, astronomers are able to measure the arrival of each X-ray from a pulsar to better than a hundred nanoseconds. From Earth, the two teams had a clear view of J0030s northern hemisphere and expected to find one hotspot there. Instead, they identified up to three, all of which were located in the southern hemisphere.

As Miller explained, these observations would not have been possible without NICERs precision:

NICERs unparalleled X-ray measurements allowed us to make the most precise and reliable calculations of a pulsars size to date, with an uncertainty of less than 10%. The whole NICER team has made an important contribution to fundamental physics that is impossible to probe in terrestrial laboratories.

This constitutes the first case of astronomers mapping out the surface of a pulsar, and the results indicate that their magnetic fields are more complicated than the traditional dipole model would suggest. While scientists have yet to determine why J0030s spots are arranged and shaped the way they are, these findings indicate that these answers could be within reach.

Even more impressive is the fact that two teams arrived at similar findings independently of one another. As Zaven Arzoumanian, the NICER science lead at NASAs Goddard Space Flight Center, expressed:

Its remarkable, and also very reassuring, that the two teams achieved such similar sizes, masses and hot spot patterns for J0030 using different modeling approaches. It tells us NICER is on the right path to help us answer an enduring question in astrophysics: What form does matter take in the ultra-dense cores of neutron stars?

As part of the Astrophysics Mission of Opportunity element of NASAs Explorers program, NICERs main scientific objective is to precisely measure the size and mass of several pulsars. This information will yield valuable clues as to what transpires within their interiors, where matter is compressed to densities that are impossible to simulate in laboratories here on Earth.

This information will also help advance astronomers understanding of black holes and other super-dense objects. The analysis of the NICER observations of J0030 has already led to a series of papers that are featured in a focus issue of The Astrophysical Journal Letters.

Be sure to check out this video that explains the researchers findings as well, courtesy of the NASA Goddard:

Further Reading: NASA

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Astronomers Map the Surface of a Pulsar - Universe Today

A team of astronomers has produced a new image of an arc-shaped object in the center of our Milky Way galaxy. The feature, which resembles a candy cane, is a magnetic structure that covers an enormous region of some 160 light-years. A light-year is the distance light travels in one year almost 6 trillion miles.

Mark Morris, a UCLA professor of physics and astronomy and a member of the research team, discovered the structure, also called the radio arc,with a former student, Farhad Yusef-Zadeh, back in 1983, but they did not have such a complete and colorful image of it then.

The new image shows the inner part of our galaxy, which houses the largest, densest collection of giant molecular clouds in the Milky Way. These vast, cool clouds contain enough dense gas and dust to form tens of millions of stars like the sun, Morris said.

In the image, blue and greenish-blue features reveal cold dust in molecular clouds where star formation is still in its infancy. Yellow features reveal the presence of ionized gas and showwherehundreds of massive stars have recently formed. Red and orange regions show areas where high-energy electrons emit radiation by a process called synchrotron emission, such as in theradio arcand Sagittarius A, the bright source at thegalaxys center that hosts its supermassive black hole.

Many of the universes secrets are being revealed through theparts of the electromagnetic spectrum of light that are not visible to the human eye. The electromagnetic spectrum encompasses the complete range of light seen and unseen from gamma rays, X-rays and ultraviolet light on one end to infrared and radio waves on the other. In the middle is the small visible spectrum that includes the colors humans can detect with the unaided eye. Gamma rays have wavelengths billions of times smaller than those of visible light, while radio waves have wavelengths billions of times longer than those of visible light. Astronomers use the entire electromagnetic spectrum. In the study that led to the new image, the research team observed radio waves with a wavelength of 2 millimeters.

The candy cane is a magnetic feature in which we can literally see the magnetic field lines illuminated by the radio emission, Morris said. The new result revealed by this image is that one of the filaments is inferred to contain extremely high-energy electrons, the origin of which remains an interesting and unsettled issue.

The candy cane arc is part of a set of radio-emitting filaments extending 160 light-years. It ismore than 100 light-years away from the central supermassive black hole. However, inanother study recently, Morris and colleagues saw similar magnetic radio filaments that they believe are connected to the supermassive black hole, which may lead to important new ways to study black holes, he said.

To produce the new image, the astronomers used a NASA 2-millimeter camera instrument called GISMO, along with a 30-meter radio telescope located at Pico Veleta, Spain. They also took archival observations from the European Space AgencysHerschel satelliteto model the infrared glow of cold dust. They added infrared data from theSCUBA-2instrument at theJames Clerk Maxwell Telescopenear the summit of Maunakea, Hawaii, and radio observations from the National Science FoundationsVery Large Array, located near Socorro, New Mexico.

The teams research describing the composite image was published last month in Astrophysical Journal.

Morris research interests include the center of the Milky Way, star formation, massive stellar clusters, and red giant stars, which are dying stars in the last stages of stellar evolution.

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Astronomers reveal new image of candy cane-shaped feature in the center of our galaxy - UCLA Newsroom