Monthly Archives: April 2021

It will take until at least 2080 before women make up just one-third of Australias professional astronomers, unless there is a significant boost to how we nurture female researchers careers.

Over the past decade, astronomy has been rightly recognised as leading the push towards gender equity in the sciences. But my new modelling, published today in Nature Astronomy, shows it is not working fast enough.

The Australian Academy of Sciences decadal plan for astronomy in Australia proposes women should comprise one-third of the senior workforce by 2025.

Its a worthy, if modest, target. However, with new data from the academys Science in Australia Gender Equity (SAGE) program, I have modelled the effects of current hiring rates and practices and arrived at a depressing, if perhaps not surprising, conclusion. Without a change to the current mechanisms, it will take at least 60 years to reach that 30% level.

However, the modelling also suggests that the introduction of ambitious, affirmative hiring programs aimed at recruiting and retaining talented women astronomers could see the target reached in just over a decade and then growing to 50% in a quarter of a century.

Before looking at how that might be done, its worth examining how the gender imbalance in physics arose in the first place. To put it bluntly: how did we get to a situation in which 40% of astronomy PhDs are awarded to women, yet they occupy fewer than 20% of senior positions?

On a broad level, the answer is simple: my analysis shows women depart astronomy at two to three times the rate of men. In Australia, from postdoc status to assistant professor level, 62% of women leave the field, compared with just 17% of men. Between assistant professor and full professor level, 47% of women leave; the male departure rate is about half that. Womens departure rates are similar in US astronomy.

Read more: 'Death by a thousand cuts': women of colour in science face a subtly hostile work environment

The next question is: why?

Many women leave out of sheer disillusionment. Women in physics and astronomy say their careers progress more slowly than those of male colleagues, and that the culture is not welcoming.

They receive fewer career resources and opportunities. Randomised double blind trials and broad research studies in astronomy and across the sciences show implicit bias in astronomy, which means more men are published, cited, invited to speak at conferences, and given telescope time.

Its hard to build a solid research-based body of work when ones access to tools and recognition is disproportionately limited.

There is another factor that sometimes contributes to the loss of women astronomers: loyalty. In situations where a womans male partner is offered a new job in another town or city, the woman more frequently gives up her work to facilitate the move.

Encouraging universities or research institutes to help partners find suitable work nearby is thus one of the strategies I (and others) have suggested to help recruit women astrophysicists.

But the bigger task at hand requires institutions to identify, tackle and overcome inherent bias a legacy of a conservative academic tradition that, research shows, is weighted towards men.

A key mechanism to achieve this was introduced in 2014 by the Astronomical Society of Australia. It devised a voluntary rating and assessment system known as the Pleiades Awards, which rewards institutions for taking concrete actions to advance the careers of women and close the gender gap.

Initiatives include longer-term postdoctoral positions with part-time options, support for returning to astronomy research after career breaks, increasing the fraction of permanent positions relative to fixed-term contracts, offering women-only permanent positions, recruitment of women directly to professorial levels, and mentoring of women for promotion to the highest levels.

Most if not all Australian organisations that employ astronomers have signed up to the Pleiades Awards, and are showing genuine commitment to change.

Seven years on, we would expect to have seen an increase in women recruited to, and retained in, senior positions.

And we are, but the effect is far from uniform. My own organisation, the ARC Centre of Excellence in All-Sky Astrophysics in 3 Dimensions (ASTRO 3D), is on track for a 50:50 women-to-men ratio working at senior levels by the end of this year.

The University of Sydney School of Physics has made nine senior appointments over the past three years, seven of them women.

But these examples are outliers. At many institutions, inequitable hiring ratios and high departure rates persist despite a large pool of women astronomers at postdoc levels and the positive encouragement of the Pleiades Awards.

Using these results and my new workforce models, I have shown current targets of 33% or 50% of women at all levels is unattainable if the status quo remains.

I propose a raft of affirmative measures to increase the presence of women at all senior levels in Australian astronomy and keep them there.

These include creating multiple women-only roles, creating prestigious senior positions for women, and hiring into multiple positions for men and women to avoid perceptions of tokenism. Improved workplace flexibility is crucial to allowing female researchers to develop their careers while balancing other responsibilities.

Read more: Isaac Newton invented calculus in self-isolation during the Great Plague. He didn't have kids to look after

Australia is far from unique when it comes to dealing with gender disparities in astronomy. Broadly similar situations persist in China, the United States and Europe. An April 2019 paper outlined similar discrimination experienced by women astronomers in Europe.

Australia, however, is well placed to play a leading role in correcting the imbalance. With the right action, it wouldnt take long to make our approach to gender equity as world-leading as our research.

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Looking at the stars, or falling by the wayside? How astronomy is failing female scientists - The Conversation AU

W. Vincent Liu, a professor in the Kenneth P. Dietrich School of Arts and Sciences Department of Physics and Astronomy, has been elected to serve the U.S.-based International Organization of Chinese Physicists and Astronomers (OCPA) on the six-year track of secretary to vice presidentto president,transitioning to thenextrole every two years.

Liu, a fellow of the American Physical Society, is interested in the theory of novel emergent phenomena of quantum condensed matter. He has considerable experience in interacting Bose and Fermi gases of cold atoms, quasionedimensional electronic, charge and/or spin liquids, and quasi 2D strongly correlated electronic systems such as high temperature superconductors. He also has a background in quantum field theory and is interested in all applications of it to condensed matter. His current research focuses on the rapidly developing field of ultracold atomic gases, driven largely by many ongoing experiments worldwide.

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W. Vincent Liu Elected to Physics and Astronomy Organization Leadership - UPJ Athletics

Scientists have discovered one of the smallest black holes on record and the closest one to Earth found to date.

Researchers have dubbed it The Unicorn, in part because it is, so far, one of a kind, and in part because it was found in the constellation Monoceros The Unicorn. The findings are publishingtoday, April 21, in the journal Monthly Notices of the Royal Astronomical Society.

When we looked at the data, this black hole the Unicorn just popped out, said lead author Tharindu Jayasinghe, a doctoral student in astronomy at The Ohio State University and an Ohio State presidential fellow.

The Unicorn is about three times the mass of our sun tiny for a black hole. Very few black holes of this mass have been found in the universe. This black hole is 1,500 light years away from Earth, still inside the Milky Way galaxy. And, until Jayasinghe started analyzing it, it was essentially hiding in plain sight.

The black hole appears to be a companion to a red giant star, meaning that the two are connected by gravity. Scientists cant see the black hole they are, by definition, dark, not only visually, but to the tools astronomers use to measure light and other wavelengths.

But in this case, they can see the black holes companion star. That star had been well-documented by telescope systems including KELT, run out of Ohio State; ASAS, the precursor to ASAS-SN, which is now run out of Ohio State, and TESS, a NASA satellite that searches for planets outside our solar system. Data about it had been widely available but hadnt yet been analyzed in this way.

When Jayasinghe and the other researchers analyzed that data, they noticed something they couldnt see appeared to be orbiting the red giant, causing the light from that star to change in intensity and appearance at various points around the orbit.

Something, they realized, was tugging at the red giant and changing its shape. That pulling effect, called a tidal distortion, offers astronomers a signal that something is affecting the star. One option was a black hole, but it would have to be small less than five times the mass of our sun, falling into a size window that astronomers call the mass gap. Only recently have astronomers considered it a possibility that black holes of that mass could exist.

When you look in a different way, which is what were doing, you find different things, said Kris Stanek, study co-author, astronomy professor at Ohio State and university distinguished scholar. Tharindu looked at this thing that so many other people had looked at and instead of dismissing the possibility that it could be a black hole, he said, Well, what if it could be a black hole?

That tidal disruption is produced by the tidal force of an unseen companion a black hole.

Just as the moons gravity distorts the Earths oceans, causing the seas to bulge toward and away from the moon, producing high tides, so does the black hole distort the star into a football-like shape with one axis longer than the other, said Todd Thompson, co-author of the study, chair of Ohio States astronomy department and university distinguished scholar. The simplest explanation is that its a black hole and in this case, the simplest explanation is the most likely one.

The velocity of the red giant, the period of the orbit and the way in which the tidal force distorted the red giant told them the black holes mass, leading them to conclude that this black hole was about three solar masses, or three times that of the sun.

For about the last decade, astronomers and astrophysicists wondered whether they werent finding these black holes because the systems and approaches they used were not sophisticated enough to find them. Or, they wondered, did they simply not exist?

Then, about 18 months ago, many of the members of this Ohio State research team, led by Thompson, published a scientific article in the journal Science, offering strong evidence that these types of black holes existed. That discovery motivated Jayasinghe and others, both at Ohio State and around the world, to search in earnest for smaller black holes. And that evaluation led them to the Unicorn.

Finding and studying black holes and neutron stars in our galaxy is crucial for scientists studying space, because it tells them about the way stars form and die.

But finding and studying black holes is, almost by definition, difficult: Individual black holes dont emit the same kind of rays that other objects emit in space. They are, to scientific equipment, electromagnetically silent and dark. Most known black holes were discovered because they interacted with a companion star, which created a lot of X-rays and those X-rays are visible to astronomers.

In recent years, more large-scale experiments to try and locate smaller black holes have launched, and Thompson said he expects to see more mass gap black holes discovered in the future.

I think the field is pushing toward this, to really map out how many low-mass, how many intermediate-mass and how many high-mass black holes there are, because every time you find one it gives you a clue about which stars collapse, which explode and which are in between, he said.

Other Ohio State researchers who co-authored this paper include Chris Kochanek, Dominick Rowan, Patrick Vallely, David Martin and Laura Lopez.

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Black hole is closest to Earth, among the smallest ever discovered - The Ohio State University News

How many black holes are there in our galaxy?

We don't know. But we can make a decent guess: We know the kinds of stars that make black holes (massive stars that explode at the ends of their lives), we know how many of those kinds of stars are born over time, and we know how old the galaxy is.

Putting that all together and doing the math, you get that the galaxy may have ten million black holes in it. Yikes.

but that number is so uncertain there could be as many as a billion of them, too. A billion black holes out there in the Milky Way!

The problem is finding them. They're black. That makes them tough to see against the blackness of space. Now, some of them orbit stars, drawing matter off that gets infernally hot and glows brightly, making them easy to spot. We know of a couple of dozen like that. That leaves 999,999,980 or so left to discover.

Enter the Nancy Roman Space Telescope.

This telescope is in the early stages now, with engineering models being built to test out the design. Scheduled for launch "in the mid-2020s" (which seems aspirational, but shouldn't be too long after that) and costing about $4 billion (including the first five years of mission costs), it's based on what NASA calls "legacy" hardware and concepts, ideas and tech developed for previous missions that have been shown to work.

Roman is very similar to the Hubble Space Telescope: It will sport a 2.4-meter primary mirror, the same size as Hubble's. But it will have a far, far wider field of view, meaning it will see larger chunks of the sky. How much bigger? In a single image it will see one hundred times as much of the sky as Hubble.

So, for example, to get the equivalent of the incredible image of the Andromeda galaxy that took Hubble 400 pointings, Roman will do in four. Yes, four.

And this is why Roman will find so many black holes. While they're dark, they have a profound effect on light that passes by them.

Light flows through space, but gravity warps space, distorting it like a bowling ball sitting on a trampoline. The path light takes going past an object will bend to follow the warp in space made by the object's gravity. The higher the gravity, the more space warps, and the more the light's path will bend.

Perhaps you see where this is going.

A black hole warps space severely. If a black hole passes between us and more distant star, for example, all manners of weird things happen to the light we see from the star. It can get amplified, making the star brighter. It can get smeared out, making the star look like a ring, or create multiple images of the star. We call this effect gravitational lensing, since gravity acts like a lens, bending the light.

That's cool, but here's the very cool bit: The Sun, that background star, and the black hole are all orbiting around the center of our galaxy, so they're all moving relative to one another. If the alignment is just so, we can actually see the star appear to move back and forth a bit on the sky as its light is bent by the passing black hole!

This won't happen hugely often because the alignment has to be fairly precise; the effect is small, with a shift of only about a milliarcsecond (one arcsecond is 1/3600th of a degree, and the full Moon on the sky is about 1,800 arseconds). Because the shift is so small we call it microlensing.

But here's where the Roman Space Telescope steps in: Its Wide-Field Imager camera looks at such a huge area of the sky (a quarter of a degree at one shot, half the width of the full Moon on the sky) with such high resolution (nearly the same as Hubble's, so sharp) and precision that just by chance it will catch this motion.

To maximize that chance astronomers will point it toward the center of the galaxy, where it will see many tens or even hundreds of millions of stars at once. By taking many images of the same field over time, any tiny shift in a star's position can be recorded. By doing this it's expected to find hundreds of solitary black holes between us and the center of the galaxy just under 26,000 light years away.

It's still a tiny fraction of the lonely dark black holes out there, but it's a whole lot more than we've seen so far. And by measuring the change in the star's position we can get the black hole's distance from us (likely thousands of light years), its mass, and it's velocity through space.

But wait! There's more!

Stars and planets can cause this gravitational lensing as well. If a solar system between us and the galactic center drifts past a more distant star, we can see the background star's brightness increase (the position shift is too small to measure). Quite a few planets thousands of light years from Earth have already been discovered this way. Roman should find a substantial number more.

Not that any of this is easy. The positions of all those stars will shift due to parallax as Roman orbits the Sun, for example, and changes in the camera's temperature can distort the detector a teeny bit (though this can be mapped very accurately and corrected). So astronomers will have their work cut out for them once Roman starts looking for these events.

Hubble Space Telescope was a revolution in astronomy. Once the focus issue was fixed it provided us with stunningly crisp and deep images of the Universe, and we leapt forward in our understanding of it.

What will the Nancy Roman Space Telescope be able to do with 100 times as much of the cosmos to see at once?

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Millions of lonely black holes are in our galaxy. Heres how well find some of them. - SYFY WIRE

IfA astronomers will help NASA generate a three-dimensional map of the universe.

University of Hawaii Institute for Astronomy (IfA) astronomers will play an instrumental role in helping unveil the universes very first galaxies, more than 13 billion light years away. On Monday, April 19, NASA announced the first suite of science programs for its groundbreaking James Webb Space Telescope (JWST), set to launch in October 2021. The IfA researchers are part of the COSMOS-Webb project, which will be the largest guest observer program in JWSTs first year of operation.

The IfA astronomers will conduct detailed follow-up observations of galaxies seen in the JWST images, using the telescopes on Maunakea. The JWST is the largest and most powerful space telescope ever built and will succeed NASAs Hubble Space Telescope. It is equipped to observe some of the most distant objects in the universe, using upgraded infrared sensitivity and resolution.

Ground-based observations from Maunakea will be critical for turning the JWST images into a three-dimensional map of the universe, said David Sanders, lead IfA investigator.

Sanders and his IfA team are part of the newly selected COSMOS-Webb program, comprised of nearly 50 researchers from 30 institutions worldwide, including IfA, the Rochester Institute of Technology (RIT), and University of Texas at Austin (UT Austin). The COSMOS-Webb program will help NASA map the first galaxies formed at Cosmic Dawn, when the universe was less than 1/20th of its current age.

Researchers will conduct spectroscopic follow-up of interesting galaxies at the W.M. Keck Observatory and Subaru Telescope. Subarus new instrument called the Prime Focus Spectrograph will be crucial for determining distances to all galaxies in the JWST survey.

The program will log more than 200 hours of observation time on Maunakea to conduct an ambitious survey of half a million galaxies. An unprecedented 32,000 galaxies will be observed using mid-infrared imaging. Researchers will rapidly release data to the public so it can lead to other studies.

The sheer scope of our program is so exciting, said IfA alumna Jeyhan Kartaltepe, a professor at RITs School of Physics and Astronomy. The first year of Webb observations will result in a lot of new discoveries that people will want to explore more in-depth in future cycles.

Much of the earlier research in this specific part of the sky has been centered at the IfA, including the S-COSMOS survey, a deep infrared imaging survey using NASAs Spitzer Space Telescope. Led by Sanders, the project was an essential precursor to this JWST program.

COSMOS-Webb has the potential to be ground-breaking in ways we havent even dreamt yet, said former IfA Hubble Fellow Caitlin Casey, now an assistant professor and COSMOS-Webb principal investigator at UT Austin. You dont know what treasures are there to find until you use an incredible telescope like Webb to stare at the sky for a long time.

COSMOS-Webb is one of just 286 general scientific observer programs NASA selected out of more than 1,000 proposals for the telescopes first year of science. These specific programs will provide the worldwide astronomical community with one of the first extensive opportunities to investigate scientific targets. JWST is slated to be operational in 2022.

For more information go to the Space Telescope Science Institute website.

This work is an example of UH Mnoas goal of Excellence in Research: Advancing the Research and Creative Work Enterprise (PDF), one of four goals identified in the 201525 Strategic Plan (PDF), updated in December 2020.

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UH astronomers to help map the first galaxies in the universe | University of Hawaii System News - UH System Current News

The mild Lyrids meteor shower has been gracing our night sky without fanfare every April, for centuries. This year, it has to tussle with a supermoon for attention

It never hurts to look up at the night sky. Stars explode, comets careen, cosmic miracles take place at an inconceivable scale far beyond our line of sight, and the only indication we get is the lightest of twinkles above our heads. Every once in a while, however, one of these phenomena deigns to enter our humble fields of vision. And while the Lyrids meteor shower is not the most exciting of them, it is among the first meteor showers of the year and one of two reasons for us to keep our eyes trained towards the sky this month.

The showers can be seen at their peak tonight (as well as a few days before and after), but their glow might be dimmed by the other phenomenon of the month: a supermoon on April 26.

What would have happened is that a comet would have broken up, probably centuries ago. We [the Earth] will be passing through the tail of the comet, or through what is left of it. This particular one is what we pass every year, around the third week of April, explains Jayant Murthy, a scientist and professor at the Bengaluru-based Indian Institute of Astrophysics, over the phone. He adds, The comet itself came by our solar system in the mid-1800s, and wont be coming back for a while.

Neeraj Ladia, head of education organisation SPACE Chennai, explains further: When the debris is left in space, it has a fixed space in the sky. Due to the Earths revolution it will cross the debris that lies in the path of its orbit. The parts of debris that encounter our atmosphere begin to burn, creating the spectacle of bright, streaking meteors.

Murthy adds that this particular shower does have a few bright fragments, and can be best viewed after midnight on a dark sky, ideally one not lit up by bright city lights. It will be brightest between April 21 and 23. Look towards the Lyra constellation to spot it, he suggests.

Major meteor showers through the year

The constellation, which the meteor shower has been named after, is considered the radiant point of the shower, explains Ladia. In simple terms, as the Earth nears this debris, that constellation is the point from where the shower appears to begin, to us.

Ladia calls this radiant point a meteor showers address in the sky. Whichever constellation it seems to be coming from, he says, is what the meteor shower is named after: Lyrids for Lyra, Geminids for Gemini, Perseid for Perseus and so on.

How powerful a meteor shower is, depends on a number of factors, such as how numerous the debris is, the size of each individual particle, its luminosity, and its rate per hour. The standard for measuring that last factor, says Ladia, is zhr or zenithal hourly rate: how many meteors can one person see per hour on a clear night. It is the measure of the quality of a meteor shower.

Lyrids has a zhr of 15 to 20 on dark skies, adds Ladia: It isnt very good, it is considered a fairly normal zhr. Geminids [in December] on the other hand has almost 120 zhr. Perseid, which is coming in August, will have around 80 meteors per hour.

He further adds that Lyrids might be even less bright this year, because of its close proximity to the supermoon. There is already a gibbous moon in the sky, which will only set around 1 am or 2 am each night, he states, adding that post-1 am is the best time to make an attempt if you live close to dark skies.

Lyrid Meteor Shower - Night astrophotography skies with light trails from streaking meteors in April.

The biggest danger of the meteor shower being drowned out by luminosity still stems from the supermoon, which also happens to be the first of its kind this year. Supermoons are generally the brightest and largest full moons of the year, and can occur two or three times a year if certain factors fall exactly into place.

Shweta Kulkarni, chief executive officer of Pune-based organisation Astron, which works to spread awareness of astronomy, explains the concept of a supermoon. The lunar orbit around the Earth is elliptical. So the moon is sometimes very close to the Earth, and sometimes moves further away during its orbit. When it is very close to us and we happen to have a full moon at the same time, we call it a supermoon.

For any satellite, the closest point of orbit to Earth is termed its perigee. According to NASA, both a new moon and a full moon can be termed a supermoon, as long as it is within 90% of perigee.

So what does this mean in visual terms? According to both Kulkarni and Ladia, it is difficult to gauge the difference between a usual full moon and a supermoon unless you put their photographs side by side.

The difference in size is just about 10% to 14%, so there isnt much to notice once its up in the sky, adds Ladia, You can tell it most drastically when the moon is still rising. Closer to the horizon, with buildings, trees or other structures for reference, it can look amazing. Space Chennai is organising a photography contest, as well as a Facebook Live on April 26. Anyone can join in and enjoy it, adds Ladia.

So you can keep your cameras and telephoto lenses ready, or you can just sit back and watch the sky and all its miracles, letting it provide some of the succour we so desperately need.

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A supermoon and a meteor shower: astronomical events this April - The Hindu