Category Archives: Astronomy

A small portion of the Veil Nebula, which is part of a supernova remnant called the Cygnus Loop, was featured in previous Hubble photos, but now new processing techniques have been applied, bringing out fine details of the Veil Nebulas delicate threads and filaments of ionized gas.

This Hubble image shows a small portion of the Veil Nebula, which is located 2,400 light-years away in the constellation of Cygnus. Image credit: NASA / ESA / Hubble / Z. Levay.

The Cygnus Loop is a large donut-shaped nebula located approximately 2,400 light-years away from Earth.

Also known as W78 and Sharpless 103, it is actually an expanding blast wave from a supernova explosion that occurred about 15,000 years ago.

Its name comes from its position in the northern constellation of Cygnus, where it covers an area 36 times larger than the full Moon.

The visual portion of the supernova remnant is known as the Veil Nebula, also called the Cirrus Nebula or the Filamentary Nebula.

The nebulas progenitor star which was 20 times the mass of the Sun lived fast and died young, ending its life in a cataclysmic release of energy, Hubble astronomers said.

Despite this stellar violence, the shockwaves and debris from the supernova sculpted the nebulas delicate tracery of ionized gas creating a scene of surprising astronomical beauty.

To create this colorful image, of the Veil Nebula observations taken by Hubbles Wide Field Camera 3 (WFC3) instrument through five different filters were used.

The new post-processing methods have further enhanced details of emissions from doubly ionized oxygen (blue), ionized hydrogen and ionized nitrogen (red).

See the article here:

Hubble Team Releases Reprocessed Image of Veil Nebula | Astronomy - Sci-News.com

Astronomers havesearched the entire Milky Way to identify the safest places to live.It turns out, we're in a pretty good spot.

But if the past year has made you feel ready to relocate to another planet, you might want to looktoward thecenter of the galaxy, according to the new research.

The new findings were made by a group of Italian astronomers, who studied locations where powerful cosmic explosions may have killed off life. These explosions, such as supernovas and gamma-ray bursts, spew high-energy particles and radiation that can shred DNA and kill life. By this logic, regions that are more hospitable to life will be the ones without frequent explosions, the astronomers reasoned.

"Powerful cosmic explosions are not negligible for the existence of life in our galaxy throughout its cosmic history," said lead author on the new study, Riccardo Spinelli, astronomer at the University of Insubria in Italy. "These events have played a role in jeopardizing life across most of the Milky Way."

Related: 11 fascinating facts about our Milky Way galaxy

In addition to finding the deadliest hotspots, the astronomers also identified the safest places throughout the galaxy's history, going back 11 billion years. The results show that we're currently at the edge of a wide band of hospitable real estate. But in the Milky Way'syouth, the galaxy's edges were a safer bet.

Many factors make a planet habitable. For instance, planets need to be in a Goldilocks zone, where heat and activity from their host star isn't too much or too little it's just right. But in addition to these local conditions, life also has to combat harmful radiation coming from interstellar space.

Powerful cosmic events, such assupernovas and gamma-ray bursts, stream dangerous, high-energy particles at nearly the speed of light. Not only can they kill all the lifeforms we know about, but these particles can also strip entire planets of their atmospheres. After such an event, the scientists believe that planets orbiting nearby star systems would be wiped clear of life.

Related: The 9 real ways Earth could end

"For planets very close to the stellar explosion it is plausible that there is a complete sterilization," Spinelli told Live Science. "In those far away, a mass extinction is more likely."

The authors wrote in the study that a nearby gamma-ray burst may have played a leading role in theOrdovician mass extinction event around 450 million years ago the second largest in Earth's history. While there is no concrete evidence linking a specific gamma-ray burst to this extinction event, the authors think it could be likely, given Earth's position in the galaxy.

Using models of star formation and evolution, the astronomers calculated when specific regions of the galaxy would be inundated with killer radiation. Early on in the galaxy's history, the inner galaxy out to about 33,000 light-years was alight with intense star formation, which rendered it inhospitable. At this time, the galaxy was frequently rocked by powerful cosmic explosions, but the outermost regions, which had fewer stars, were mostly spared these cataclysms.

Until about 6 billion years ago, most of the galaxy was regularly sterilized by massive explosions. As the galaxy aged, such explosions became less common. Today, the mid regions, forming a ring from 6,500 light-years from the galaxy's center to around 26,000 light-years from the center, are the safest areas for life. Closer to the center, supernovas and other events are still common, and in the outskirts, there are fewer terrestrial planets and more gamma-ray bursts.

Luckily for us, our galactic neighborhood is getting more and more life-friendly. In the long-term galactic future, there will be fewer extreme events nearby that could cause another mass extinction.

The new paper's conclusions seem reasonable at first glance, Steven Desch, an astrophysicist at Arizona State University, told Live Science.

"I'm pleased to note that they do seem to put [the research] in a rigorous framework and have realistic expectations about what a gamma ray burst would do, and account for factors that sometimes people forget," such as how the energy and material released by gamma-ray bursts isnt equal in all directions, said Desch, who was not involved with the new work. "I haven't gone through their numbers in detail, but at first glance it's reasonable."

The new research, published in the March issue of the journal Astronomy and Astrophysics, might one day help astronomers decide where to search for habitable exoplanets. But for now technology limits astronomers to only searching nearby areas, Desch said.

Originally published on Live Science.

Original post:

Astronomers find the 'safest place' to live in the Milky Way - Livescience.com

YOUNGSTOWN Warren Young passionately recalled when he and Ted Pedas had witnessed a total solar eclipse nearly 50 years ago. At no time since then had anything gotten in the way of their longtime friendship.

He was a guy who took his job very seriously, said Young, a retired Youngstown State University professor who was the universitys original Ward Beecher Planetarium director from 1967 to 2004.

Seeing the rare celestial event with Pedas in July 1972 aboard a cruise ship off the coast of Africa is one of many fond memories Young has of his relationship with Pedas, an astronomy educator, philanthropist and entrepreneur who died March 11 of sudden cardiac arrest at his winter home in Sanibel Island, Fla. He was 82.

Young, who also served as chairman of YSUs physics department, remembered having met on the ship Neil Armstrong, who was the first person to walk on the moon, along with several well-known science writers.

One of the things (Pedas) had me do was introduce Neil Armstrong. I talked to him about the moon, and it was like talking to Columbus after he discovered the New World, Young said, adding that Pedas loved conducting astronomy-related lectures aboard cruise ships.

Pedas, whom Young hired at the planetarium in the late 1960s after Pedas had earned a degree from Michigan State University, also had a gift for interesting people in astronomy largely by meeting them at their age levels. For example, he had young children learn the basics about meteorites while allowing them to touch the bits of space material, Young said, adding Pedas ran astronomy shows for people of all ages, as well as school groups, several times weekly.

In 1993, after several decades at the Ward Beecher Planetarium, he was designated planetarium administrator emeritus. Pedas also was one of the International Planetarium Societys founding members in 1968.

The IPS is a global association of astronomers and other planetarium professionals. Its nearly 500 members from 50 countries represent schools, museums, universities and public facilities, including planetariums, the organizations website states.

Pedas earned degrees in planetarium science and science education from YSU, Michigan State and the University of California at Berkeley.

His entrepreneurship was evident in many ways, including donating money to, and conducting shows at, Farrell High Schools planetarium, which was renamed the Ted Pedas Planetarium largely because of his benevolence and donations to the Farrell Area School District. He also gave money for awards students were to receive, Young continued.

SPACE AGE INTEREST

Teds education and subsequent interests initially began with the start of the Space Age in the mid-1950s, Kaoru Kimura, who lives in Tokyo and is president of the International Planetarium Society, said in a statement. He combined a talent for business with a passion for teaching, particularly astronomy and space science in his hometown of Farrell, Pennsylvania.

Anthony F. Tony Aveni, an astronomy and anthropology professor at Russell Colgate University in Hamilton, N.Y., recalled that about 50 years ago, Pedas called to ask him to conduct lectures about astronomy on a cruise ship. That led to Aveni and his wife, Lorraine, spending winters in that pursuit until the pandemic began last year, he remembered.

Anyone who lives within a light year of Youngstown is well aware of Teds generosity, said Aveni, whos also a lecturer as well as editor and author of more than 20 books on ancient astronomy.

In addition, Aveni helped develop the field of archeoastronomy, the study of how ancient people came to understand astronomical events, as well as how they used and interpreted such phenomena in their cultures.

Pedas great knowledge and stellar love for his subject reverberated not only in the classroom or aboard large cruise ships, but to newspaper readers and a large segment of the public, said Sharon Shanks, who met Pedas in 1990 before succeeding him as a Ward Beecher Planetarium lecturer until she retired in 2015.

Not only did I follow him as a lecturer, but also as author of The Cosmos for The Vindicator from 1996 to 2002, Shanks remembered. He educated hundreds of thousands of people about astronomy and promoted the planetarium through that weekly column, which he wrote out by hand on yellow legal pads. He realized there was a thirst for knowledge about space and astronomy among people, and that many enjoyed learning regardless of their age.

Shanks, who retired last December after having worked 14 years as editor of Planetarian, the International Planetarium Societys journal, added that she enjoyed assisting Pedas with his cruise endeavors. In addition, Shanks lectured on two such journeys and for several years, taught once per week at the Farrell High School Planetarium for Pedas.

The 146-seat planetarium at YSU, which opened in 1967, is the first in the U.S. thats also set up as a classroom. It has undergone four major renovations, including one in 2017 to upgrade its video system, Curtis Spivey, planetarium engineer, noted.

In 2019, an estimated 20,000 people attended a variety of shows before the pandemic began last March and it had to close to the public, Spivey said, adding he hopes the facility will be able to fully reopen by fall. Now its being used in a limited capacity for students taking a basic astronomy class, he continued.

For more information about the Ward Beecher Planetarium, go to http://www.wbplanetarium.org., or visit its Facebook page.

news@tribtoday.com

Today's breaking news and more in your inbox

Read the rest here:

YSU's star of the stars remembered | News, Sports, Jobs - Youngstown Vindicator

This is an artists impression created to visualize the concentration of black holes at the center of NGC 6397. In reality, the small black holes here are far too small for the direct observing capacities of any existing or planned future telescope, including Hubble. It is predicted that this core-collapsed globular cluster could be host to more than 20 black holes. Credit: ESA/Hubble, N. Bartmann

Astronomers found something they werent expecting at the heart of the globular cluster NGC 6397: a concentration of smaller black holes lurking there instead of one massive black hole.

Globular clusters are extremely dense stellar systems, which host stars that are closely packed together. These systems are also typically very old the globular cluster at the focus of this study, NGC 6397, is almost as old as the universe itself. This cluster resides 7,800 light-years away, making it one of the closest globular clusters to Earth. Due to its very dense nucleus, it is known as a core-collapsed cluster.

At first, astronomers thought the globular cluster hosted an intermediate-mass black hole. These are the long-sought missing link between supermassive black holes (many millions of times our Suns mass) that lie at the cores of galaxies, and stellar-mass black holes (a few times our Suns mass) that form following the collapse of a single massive star. Their mere existence is hotly debated.Only a few candidates have been identified to date.

The amount of mass a black hole can pack away varies widely from less than twice the mass of our Sun to over a billion times our Suns mass. Midway between are intermediate-mass black holes weighing roughly hundreds to tens of thousands of solar masses. So, black holes come small, medium, and large. Credit: NASA, ESA, T. Brown, S. Casertano, and J. Anderson (STScI)

We found very strong evidence for an invisible mass in the dense core of the globular cluster, but we were surprised to find that this extra mass is not point-like (that would be expected for a solitary massive black hole) but extended to a few percent of the size of the cluster, said Eduardo Vitral of the Paris Institute of Astrophysics(IAP) in Paris, France.

To detect the elusive hidden mass, Vitral and Gary Mamon, also of IAP, used the velocities of stars in the cluster to determine the distribution of its total mass, that is the mass in the visible stars, as well as in faint stars and black holes. The more mass at some location, the faster the stars travel around it.

The researchers used previous estimates of the stars tiny proper motions (their apparent motions on the sky), which allow for determining their true velocities within the cluster. These precise measurements for stars in the clusters core could only be made with Hubble over several years of observation. The Hubble data were added to well-calibrated proper motion measurements provided by the European Space Agencys Gaia space observatorywhich are less precise than Hubbles observations in the core.

Our analysis indicated that the orbits of the stars are close to random throughout the globular cluster, rather than systematically circular or very elongated, explained Mamon. These moderate-elongation orbital shapes constrain what the inner mass must be.

Astronomers on the hunt for an intermediate-mass black hole at the heart of the globular cluster NGC 6397 found something they werent expecting: a concentration of smaller black holes lurking there instead of one massive black hole. Credit: NASA Goddard Space Flight Center

The researchers conclude that the invisible component can only be made of the remnants of massive stars (white dwarfs, neutron stars, and black holes) given its mass, extent,and location. These stellar corpses progressively sank to the clusters center after gravitational interactions with nearby less massive stars. This game of stellar pinball is called dynamical friction, where, through an exchange of momentum, heavier stars are segregated in the clusters core and lower-mass stars migrate to the clusters periphery.

We used the theory of stellar evolution to conclude that most of the extra mass we found was in the form of black holes, said Mamon. Two other recent studies had also proposed that stellar remnants, in particular, stellar-mass black holes, could populate the inner regions of globular clusters. Ours is thefirst study to provide both the mass and the extent of what appears to be a collection of mostly black holes in the center of a core-collapsed globular cluster, added Vitral.

The astronomers also note that this discovery raises the possibility that mergers of these tightly packed black holes in globular clusters may be an important source of gravitational waves, ripples through spacetime. Such phenomena could be detected by the Laser Interferometer Gravitational-Wave Observatory experiment, which is funded by the National Science Foundation and operated by Caltech in Pasadena, Californiaand MIT inCambridge, Massachusetts.

For more on this research, read Unexpected Discovery: Hubble Space Telescope Uncovers Concentration of Small Black Holes.

Reference: Does NGC 6397 contain an intermediate-mass black hole or a more diffuse inner subcluster? by Eduardo Vitral and Gary A. Mamon, 11 February 2021, Astronomy and Astrophysics.DOI: 10.1051/0004-6361/202039650

The Hubble Space Telescope is a project of international cooperation between NASA and ESA (European Space Agency). NASAs Goddard Space Flight Center in Greenbelt, Maryland, manages the telescope. The Space Telescope Science Institute (STScI) in Baltimore, Maryland, conducts Hubble science operations. STScI is operated for NASA by the Association of Universities for Research in Astronomy in Washington, D.C.

Go here to read the rest:

Astronomers Make a Weird Discovery: A Concentration of Smaller Black Holes Lurking Where They Expected a Single Massive Black Hole - SciTechDaily

A black hole in the Cygnus X-1 binary system is so massive that it challenges current stellar evolution models.

An artists impression of the Cygnus X-1 binary system. Image credit: International Centre for Radio Astronomy Research.

Discovered in 1964, Cygnus X-1 is an X-ray binary system located in the constellation Cygnus.

The primary star, HD 226868, is a hot supergiant revolving about an unseen compact companion with a period of 5.6 days.

The companion is a so-called stellar-mass black hole, a class of black holes that comes from the collapse of a massive star.

Cygnus X-1 was the focus of a famous scientific wager between physicists Stephen Hawking and Kip Thorne, with Hawking betting in 1974 that it was not a black hole. Hawking conceded the bet in 1990.

Stars lose mass to their surrounding environment through stellar winds that blow away from their surface, said Professor Ilya Mandel, an astrophysicist at Monash University and the ARC Centre of Excellence in Gravitational Wave Discovery (OzGrav).

But to make a black hole this heavy, we need to dial down the amount of mass that bright stars lose during their lifetimes.

The black hole in the Cygnus X-1 system began life as a star approximately 60 times the mass of the Sun and collapsed tens of thousands of years ago, he added.

Incredibly, its orbiting its companion star a supergiant every five and a half days at just one-fifth of the distance between the Earth and the Sun.

Professor Mandel and colleagues observed Cygnus X-1 using the Very Long Baseline Array (VLBA).

Using the new VLBA data and archival observations, they refined the distance to the binary system and found it to be farther away than previously estimated, thus raising the inferred mass of the systems black hole to 21.2 solar masses.

Over six days we observed a full orbit of the black hole and used observations taken of the same system with the same telescope array in 2011, said Professor James Miller-Jones, an astronomer at Curtin University and the International Centre for Radio Astronomy Research (ICRAR).

This method and our new measurements show the system is further away than previously thought, with a black hole thats significantly more massive.

These new observations tell us the black hole is more than 20 times the mass of our Sun a 50% increase on previous estimates, Professor Mandel said.

Using the updated measurements for the black holes mass and its distance away from Earth, we were able to confirm that Cygnus X-1 is spinning incredibly quickly very close to the speed of light and faster than any other black hole found to date, said Xueshan Zhao, a Ph.D. candidate studying at the National Astronomical Observatories of the Chinese Academy of Sciences.

The findings were published in the journal Science.

_____

James C.A. Miller-Jones et al. Cygnus X-1 contains a 21-solar mass black hole Implications for massive star winds. Science, published online February 18, 2021; doi: 10.1126/science.abb3363

The rest is here:

Cygnus X-1's Stellar-Mass Black Hole is More Massive than Astronomers Thought | Astronomy - Sci-News.com

Where the heck is the neutron star that should be in the middle of the debris from Supernova 1987A?

It's one of the bigger mysteries of modern astronomical times. On the night of February 23/24, 1987 (essentially 34 years ago today, so happy anniversary!) the light from an exploding star reached Earth. Dubbed Supernova 1987A, it came from the Large Magellanic Cloud, a satellite galaxy of the Milky Way just 160,000 light years away. That's close enough that the supernova was visible to the naked eye, and it became one of the most well studied astronomical objects in history*.

The star that blew up was massive, probably about 20 times the mass of the Sun. When a star like that reaches the end of its life it blows a series of powerful winds of gas that surround it. Some tens of thousands of years later the core of the star collapses, setting up an immense explosion that blasts away its outer layers: Supernova.

The collapsing core of a massive star can become either a black hole or an incredibly dense neutron star. In this case, it should've formed the latter.

Newborn neutron stars have powerful magnetic fields and spin rapidly. They blast out beams of high-energy radiation like sweep around like a lighthouse beam, which we see when they pass over us. We get blips of radiation like pulses, so these young neutron stars are called pulsars. They're usually pretty obvious (like a baby screaming on an airplane; the source isn't too tough to spot). But in this case, despite intense searches for over three decades, no neutron star has been found.

However, in the past couple of years evidence is starting to come in. A blob of radio emission was seen recently that could be from the baby neutron star, but it's not 100% certain. Now, astronomers have gone over some archived X-ray observations taken from 2012 2014 and find that they too point toward the X-rays coming from the neutron star.

X-rays are a form of light, like the light we see but with far higher energies. It takes powerful events to create them. In a young supernova they could be from the blast wave generated by the expanding debris from the explosion slamming into the gas outside it, or they could be from a seriously strong wave of particles, called the pulsar wind nebula, accelerated by the neutron star's ridiculously fierce magnetic field.

The astronomers looked at the X-ray observations from two space-based observatories, the Chandra X-ray Observatory and NuSTAR. Chandra sees relatively low energy X-rays, and NuSTAR much higher energy ones.

What they found is that the X-ray spectrum the brightness of the X-rays versus their energy from the two observatories combined showed that the low-energy X-rays were consistent with the blast wave idea. But if that were the case they'd expect very few high-energy X-rays. However the spectrum clearly shows more high-energy ones than expected.

That leans more toward the idea these X-rays are coming from the pulsar wind, which emits far more high-energy X-rays. The spectrum by itself isn't conclusive. However, we also have a grasp of what's going on physically inside the supernova, and it's much easier to match the spectrum to the physics of a pulsar wind than a blast wave. That's also not conclusive, but it gives a lot more credence to the existence of a neutron star in the middle of all that junk.

There's a way to know better too. All the dense material surrounding the center of the explosion is blocking our view somewhat. Over time that material expands and gets less dense. Like a fog clearing, that should allow more high-energy X-rays through. If we see the higher energy X-rays get brighter, that would strongly favor the pulsar wind model. If instead they get fainter that favors the blast wave idea (which should fade more rapidly over time). Hopefully future NuSTAR observations can settle this question.

We see neutron star pulsars in the centers of many supernova remnants (like the famous Crab Nebula pulsar, or the one in the Vela supernova remnant), and they are an important factor in the shaping and evolution of the rapidly expanding debris from the explosion. The gas around Supernova 1987A, blown by the star before it died, is a bit bizarre, shaped like a huge hourglass with a dense ring in the middle. The actual stellar debris is in the middle of all that, and will slam into this gas over the next few centuries.

If there's a pulsar in there, its vast stores of energy will accelerate that material in the collision like hitting the gas in a car. If we want to understand how this interaction will occur and oh my we do, since it's the closest such supernova in centuries then we need to know if there's a neutron star in the middle of all that and what's its doing to add to the chaos. Hopefully soon we'll find out.

*Three years later the newly launched Hubble Space Telescope made SN1987A one of its very first targets; I used those and subsequent observations to get my PhD in astronomy, so this topic is close to me.

Read the original post:

Is there an angry baby neutron star in the middle of Supernova 1987A? - SYFY WIRE

This is an automated machine translation of an article published by Business Insider in a different language. Machine translations can generate errors or inaccuracies; we will continue the work to improve these translations. You can find the original version here.

Astronomy wants to become a field open to the whole of society, not only to observe stars and planets but also to prevent the destruction of the planet itself due to an unplanned impact.

This is the goal of Unistellar Optics, the company that has developed the eVscope home telescope, so that, from the comfort of one's home, anyone can look up at the vast universe that looms over humanity.

In a compelling tone, the company launched a challenge to observe the trajectory of Apophis on February 21, the day it was hidden behind a star, so it could be observed; moreover, it will pass dangerously close to the Earth and the Moon by the year 2029, 2036 and 2068, the latter being the one with the highest risk of impact.

To do so, they launched the challenge of observing the "infamous" Asteroid 99942 Apophis. They wonder if it would be capable of destroying orbital satellites or directly impacting the Earth's atmosphere.

Thus, Apophis has been classified as a Potentially Hazardous Asteroid -PHA-, since, in 2029, it is expected to pass 31,860 kilometers away from the Earth's surface.

By 2029, Apophis' orbit is expected to change due to its approach to Earth and the Moon.

These predictions have been joined by the latest ones made by NASA's CNEOS center, in charge of cataloging objects at risk of impact, which has observed how this has decreased thanks to the so-called Yarkovsky effect, by which the orbit of a small object in the Solar System is modified due to the absorption of solar radiation.

From iguanas to fireballs: 7 strange things that have fallen from the sky

"One of the great mysteries about Apophis is how its orbit changes when the asteroid is illuminated by the Sun; this Yarkovsky effect is very difficult to simulate, so direct observation of an occultation - the asteroid passes in front of a star - will give us greater precision of the asteroid's position," explained Franck Marchis, senior astronomer at the SETI Institute (USA) and chief scientist at Unistellar, in a statement.

This effect has been observed by astronomers at the University of Hawaii (United States), who update almost daily the data on the risk probabilities, as well as the danger of a possible collision in 2068, the expected date of impact.

Observing Apophis, the "god of chaos," is a vitally important action for the Earth, as the asteroid belongs to the subgroup of those that pass dangerously close to the planet, known as Aton asteroids.

In addition, many of them are categorized as potentially hazardous and, specifically, Apophis has a diameter of 340 meters, which poses a greater risk.

Since its discovery in 2004 by Dave Tholen and astronomers at the University of Hawaii, thanks to the Subaru telescope on Maunakea, Apophis has been closely followed, including these recent changes due to the Yarkovsky effect.

Unfortunately, astronomers used the Arecibo telescope (Puerto Rico) to observe objects like these, although it was dismantled in 2020, after several technical failures in its structure.

For this reason, Unistellar asked for help from the public and, in particular, from amateur astronomers, so that no details would be missed by the official Apophis researchers.

On the other hand, although the asteroid could be observed last February 21 across the United States, help from the public is still welcome, as the risk of Apophis impact remains active for the next few years.

Only the collaboration of all the people will be able to really defend the terrestrial citizens, who have their first enemy in this asteroid, the most dangerous that has ever grazed the Earth.

More here:

Planetary defense plan activated: astronomers appeal to observe Apophis asteroid, which will graze Earth in... - Business Insider

The American Astronomical Society (AAS) is making the most of online opportunities during its 237th meeting, which will fully take place virtually this week due to the coronavirus pandemic.

The self-proclaimed "Super Bowl of Astronomy," which runs through Friday (Jan. 15), typically covers a wide range of topics, and this year's edition will be no different even though it will be fully online. The full agenda is available here. Some hot topics attendees can expect include fast radio bursts, dark matter, sky surveys, gravitational waves, and trying to understand why different teams have different measurements to calculate the expansion of the universe, among others.

AAS was already including iPosters (PowerPoint-like posters with combinations of text, images, video and audio) at its in-person meetings, along with short science talks, before the pandemic erupted last March. The society tested these meeting formats online with the June 2020 meeting, which was quickly moved online only weeks before starting as quarantine restrictions expanded across the United States.

Full coverage: The 237th American Astronomical Society meeting of 2021

Attendees can expect even more adaptations to online for AAS 237, press officer Rick Fienberg told Space.com in an e-mail interview.

"For AAS 237, we are adding 'Turbo Talks' 2-minute introductory videos by authors to draw attention and spur interest in their iPosters," he said. Other changes attendees can expect include Slack channels during the talks for people to "kibitz", Fienberg said, and spreading the meeting over five days instead of four to reduce the time attendees must spend at the computer each day.

The virtual exhibition hall will be very different than what attendees saw in June. This time around, AAS will use a meeting environment called vFairs, which allows sponsors and exhibitors to create custom-branded virtual booths, Fienberg said.

"They can post brochures and other files for download, have staff at the booth at certain times of day to interact with attendees one-on-one or in small groups, and offer webinars to introduce larger audiences of attendees to their products and services," he said.

Coronavirus and space: How the pandemic is affecting research and missions

The ultimate goal is to attract more attendees to the virtual exhibition hall, mirroring the "coffee break" and "cocktail hour" experience one typically gets by wandering into the physical hall during an in-person meeting, he added.

"At our first virtual meeting in June, exhibitors didn't get the traffic theyre used to, for obvious reasons," Fienberg said. "So for January, we've set aside some dedicated time each day where the only activity is in the exhibit hall, and we've successfully encouraged nearly all our exhibitors to offer webinars, which are being listed in the program along with everything else so as not to get lost in the shuffle."

Student attendees can also look forward to the first-ever virtual "graduate school" and undergraduate research "experience fair" which will allow students to share CVs, meeting via text and video chat, and learn more about participating institutions all without the need of paying for in-person travel. People at all stages of their career can also take advantage of various social networking events, such as a trivia night, speed networking and a virtual scavenger hunt.

Looking back at the June meeting, Fienberg said the AAS staff "really had to scramble" to shift all activities online, including assembling the infrastructure, find vendors, and to bring members and other stakeholders along for the ride. The hard work paid off, as roughly 1,400 people attended the virtual activities double the expected attendance AAS thought it would see in-person in Madison, Wisc.

Fienberg said AAS has listened closely to attendee feedback in June to prepare for January; another change they are making is including two days of workshops that were not offered in June. The winter meeting typically has higher attendance than the summer meeting, with more sessions and activities as well.

"With five days of science sessions and two slots daily for press conferences, Ive scheduled 10 briefings rather than my usual eight, so I have 25% more presenters to communicate with plus their institutional public information officers," Fienberg said. "All of us involved in planning and executing the meeting are really quite exhausted already, but that's true when doing in-person meetings too. What we've learned over these two meetings is that a virtual meeting involves just as much work as an in-person one."

Fienberg added that some attendees have expressed worry about high registration fees for the virtual meeting, but he noted the infrastructure is not free. While venues and caterers are not required for online conferences, AAS is still working with vendors and software to deliver the best experience possible. "It's a fairly even trade," he said of the cost to AAS.

With a vaccine slowly rolling out in the United States and other countries, AAS is thinking ahead to when in-person meetings will be possible again in the coming months. Even before the pandemic erupted, members already were asking for virtual options due to cost and environmental concerns associated with activities like flying, Fienberg said. Journalists have been able to attend virtual press conferences for many years now, and Fienberg said the pandemic has caused even more types of attendees to strongly consider the online option.

"I think its inevitable that the meeting of the future will be hybrid," he said. "We just have to figure out how to make it work financially."

Follow Elizabeth Howell on Twitter @howellspace. Follow us on Twitter @Spacedotcom and on Facebook.

View original post here:

'Super Bowl of Astronomy' kicks off online due to global pandemic - Space.com

News releases | Research | Science

January 14, 2021

The sun is the only star in our system. But many of the points of light in our night sky are not as lonely. By some estimates, more than three-quarters of all stars exist as binaries with one companion or in even more complex relationships. Stars in close quarters can have dramatic impacts on their neighbors. They can strip material from one another, merge or twist each others movements through the cosmos.

And sometimes those changes unfold over the course of a few generations.

That is what a team of astronomers from the University of Washington, Western Washington University and the University of California, Irvine discovered when they analyzed more than 125 years of astronomical observations of a nearby stellar binary called HS Hydrae. This system is whats known as an eclipsing binary: From Earth, the two stars appear to pass over one another or eclipse one another as they orbit a shared center of gravity. The eclipses cause the amount of light emitted by the binary to dim periodically.

An image from the Digitized Sky Survey showing HS Hydrae in the center.Space Telescope Science Institute

On Jan. 11 at the 237th meeting of the American Astronomical Society, the team reported more than a centurys worth of changes to the eclipses by the stars in HS Hydrae. The two stars began to eclipse in small amounts starting around a century ago, increasing to almost full eclipses by the 1960s. The degree of eclipsing then plummeted over the course of just a half century, and will cease around February 2021.

There is a historical record of observations of HS Hydrae that essentially spans modern astronomy starting with photographic plates in the late 19th century up through satellite images taken in 2019. By diving into those records, we documented the complete rise and fall of this rare type of eclipsing binary, said team leader James Davenport, a research assistant professor of astronomy at the UW and associate director of the UWs DIRAC Institute.

The eclipses of the two stars that make up HS Hydrae are changing because another body most likely a third, unobserved companion star is turning the orientation of the binary with respect to Earth. Systems like this, which are called evolving eclipsing binaries, are rare, with only about a dozen known to date, according to Davenport. Identifying this type of binary requires multiple observations to look for long-term changes in the degree of dimming, which would indicate that the orientation of the binary is changing over time.

HS Hydrae has such an observational record because, at 342 light- years away, it is a relatively close and bright system and the two stars orbit each other every 1.5 days. Scientists first reported that HS Hydrae was an eclipsing binary in 1965. In a 2012 paper, astronomers based in Switzerland and the Czech Republic reported that the amount of dimming from HS Hydrae decreased from 1975 through 2008, indicating that the two stars were eclipsing smaller and smaller portions of one another over time. That team also predicted that the eclipses would end around 2022.

Davenport and his team checked in on HS Hydrae using observations of the system in 2019 by the NASAs Transiting Exoplanet Survey Satellite, or TESS. They saw only a 0.0075-magnitude drop in light from HS Hydrae, a sign that the two stars were barely covering one another during eclipses. For comparison, eclipses in 1975 saw a more than 0.5-magnitude drop.

Fifty years ago, these two stars were almost completely eclipsing each other. By the early 21st century, the degree of eclipse was around 10%, and in the most recent observations from 2019, they barely overlapped, said Davenport.

With these new data, the team now predicts that HS Hydrae eclipses will cease around February 2021.

Image of a photographic plate from 1945, which was digitized for the Digital Access to a Sky Century at Harvard, or DASCH, catalog.DASCH/Harvard University

The observations from the 1960s through 2019 catalogue the decline of HS Hydrae as an evolving eclipsing binary. But Davenport and his team also uncovered evidence for its rise. The Digital Access to a Sky Century at Harvard, or DASCH, is a digital catalog of photometric data taken from more than a centurys worth of astro-photographic plates at Harvard University. The team mined this record and found observations of HS Hydrae from 1893 through 1955 that they could analyze to search for signs of dimming.

The researchers broke down DASCH observations of HS Hydrae by decade. From the late 19th century through the roaring 20s, HS Hydrae showed no measurable dimming. But things began to change in the 1930s, where they measured a modest 0.1-magnitude drop in brightness. The degree of dimming rose through the 1940s and peaked in the 1950s with a 0.5-magnitude drop in brightness.

Based off this 126-year history of HS Hydrae observations, the team predicts that the system will start eclipsing again around the year 2195. But, that assumes that the third companion which other teams have predicted is a small, dim M-dwarf star continues to behave as it has to date.

Image of an astronomical log book from 1945. These observations are now part of the Digital Access to a Sky Century at Harvard, or DASCH, catalog.DASCH/Harvard University

We wont know for sure unless we keep looking, said Davenport. The best we can say right now is that HS Hydrae has been changing constantly over the course of modern astronomy.

Missions like TESS will likely identify more evolving eclipsing binaries in the coming years. This should open new opportunities for astronomers to understand how star systems are built, as well as how they change over time whether they are busy, dynamic systems like HS Hydrae, or more quiet systems, like ours.

Co-authors on the paper are UW graduate students Diana Windemuth and Jessica Birky; UW researcher Karen Warmbein; Erin Howard at Western Washington University; and Courtney Klein at UC Irvine. The research was funded by NASA, the National Science Foundation, the Heising-Simons Foundation, the Research Corporation for Science Advancement, the DIRAC Institute, the UW Department of Astronomy, the Charles and Lisa Simonyi Fund for Arts and Sciences and the Washington Research Foundation.

For more information, contact Davenport at jrad@uw.edu.

Read more from the original source:

Astronomers document the rise and fall of a rarely observed stellar dance - UW News

Astronomers have, for the first time, witnessed the death of a distant galaxy, which they describe as a "truly extreme event."

When all of the stars in a galaxy die, and new ones are no longer forming, the galaxy itself ceases to exist. This occurs when all of the galaxy's gas is ejected, making it impossible for new stars to form.

According to a study published Monday in the journal Nature Astronomy, scientists were "thrilled" to be able to capture this rare phenomenon recently using the Atacama Large Millimeter/submilimeter Array of telescopes in Chile.

It has taken about nine billion years for the light from the starburst galaxy ID2299 to reach Earth. So, when astronomers happened to observe it by chance, they witnessed the universe as it appeared at just 4.5 billion years old.

Astronomers say that ID2299 is losing 10,000 suns worth of gas each year rapidly depleting fuel needed to form new stars. This startling release of gas appears to be the result of two galaxies violently colliding and merging together to create ID2299.

The galaxy is also currently forming stars at a rate hundreds of times faster than the Milky Way using up the rest of its precious gas supply. Because of this, ID2299 is expected to die relatively soon, in just a few tens of thousands of years.

"This is the first time we have observed a typical massive star-forming galaxy in the distant universe about to 'die' because of a massive cold gas ejection," lead author Annagrazia Puglisi said in a statement.

Astronomers believe the phenomenon is the result of galaxies merging because they were able to witness a rare "tidal tail," usually too faint to see in distant galaxies. This elongated stream of stars and gas, astronomers suggest, is the direct result of the galactic merger.

They only observed the galaxy for a few minutes, but it was enough to spot the elusive tidal tail.

"Our study suggests that gas ejections can be produced by mergers and that winds and tidal tails can appear very similar," says study co-author Emanuele Daddi. "This might lead us to revise our understanding of how galaxies 'die.'"

If the astronomers are correct that the merger led to the massive loss of gas, they will need to reconsider prior theories on how galaxies form and evolve and how they die. Other theories have suggested that wind from active black holes or intense star formations are responsible for such deaths.

"Studying this single case unveiled the possibility that this type of event might not be unusual at all and that many galaxies suffered from this 'gravitational gas removal', including misinterpreted past observations,"said co-author Dr. Jeremy Fensch.

"This might have huge consequences on our understanding of what actually shapes the evolution of galaxies."

Go here to read the rest:

Astronomers observe the death of a distant galaxy for the first time - CBS News