Category Archives: Astronomy

ByHub staff report

Legendary investor and philanthropist William H. "Bill" Miller III has made a lead gift of $50 million in a combined $75 million philanthropic effort to support Johns Hopkins University's Department of Physics and Astronomy.

Miller's $50 million commitment will fund endowed professorships, postdoctoral fellowships, and graduate research, and will provide ongoing support for research infrastructure. His gift also served as the impetus for two anonymous donors to support the department as well, expanding to $75 million the funding to advance key areas of physics research.

Image caption: William H. "Bill" Miller III

The gift will propel one of the nation's most storied departments of physics to new heightsexpanding research into emerging subfields of study and attracting promising young researchers, Johns Hopkins University President Ron Daniels said.

"The support Bill Miller has shown Johns Hopkins is historic," Daniels said. "Four years ago, Mr. Miller committed what is believed to be the largest ever gift to a university philosophy program, and now he has made an equally impressive gift to the study of physics and astronomy. We are endlessly grateful for his generosity that is driving our scholars to explore everything from the human condition to our understanding of the universe and our place in it. A philanthropic investment of this magnitude will be a standard-bearer for how a robust physics and astronomy department can broaden its research, engage in collaborative exploration, and advance to the front lines of emerging areas."

Said Miller: "Physics seeks to understand reality at its most fundamental level. It is the bedrock on which the other sciences rest. I am delighted to be able to make a gift to Johns Hopkins physics that will enable it to add new resources and continue to build on its distinguished history."

At the center of Miller's gift is funding for young scientists. Support for these future leaders in physics and astronomy includes the creation of 10 prize postdoctoral fellowships and 10 endowed graduate research fellowships. The gift will also support the establishment of three endowed professorships, a cohort of senior and junior level faculty lines, and funding for research infrastructure such as laboratory equipment and instrumentation. In all, this new philanthropic support will enable the department to grow from its current 33 faculty to 46 over the next five years.

"The visionary research currently underway in our physics and astronomy department will be enhanced by this gift in vital ways that could potentially change our view of the universe," said Chris Celenza, dean of the university's Krieger School of Arts and Sciences, of which the Department of Physics and Astronomy is a part. "Mr. Miller's extraordinary gift will enrich the scholarly and collaborative pursuits of our faculty and students for decades to come."

The Department of Physics and Astronomy has a notable history dating back to 1876, when it became the first physics department in the United States dedicated to research. One of the most significant events in the department's modern history occurred in 1981, when NASA chose Johns Hopkins as the site for the Space Telescope Science Institute. This decision transformed Johns Hopkins into one of the nation's premier centers for astronomy and also raised the profile of the physics department, which embraced a name change in 1984 to the Department of Physics and Astronomy. In 1991, the department moved into its current space, the Bloomberg Center for Physics and Astronomy, complete with a rooftop observatory dome that is home to the Morris W. Offit Telescope. The department has attracted numerous remarkable faculty members, including two Nobel laureates and recipients of prestigious global awards such as the Gruber Cosmology Prize, the Simons Investigator Award, and a McArthur Fellowship.

Today, the department's expertise is distributed in three primary areas: astronomy, condensed matter physics, and particle physics. Its experimental and theoretical faculty members are renowned for their work in areas such as astrophysics, cosmology, big data, quantum materials, extra-galactic astronomy, particle-theory model building, and dark matter detection.

"Because of Mr. Miller's gift, Johns Hopkins will be an even more enticing place for young physics students and scholars to learn from our preeminent physicists," said Timothy Heckman, professor and department chair. "Our faculty, in turn, will have the privilege of preparing the next generation of brilliant physicists. Such a financial venture will have an astounding impact on discovery that could potentially reveal new truths about some of the deep mysteries of the universe and how we live in it."

In recognition of Miller's gift, the department will be renamed the William H. Miller III Department of Physics and Astronomy. The department currently carries an honorific naming in recognition of the department's first chair, Henry A. Rowland, who was known as one of the most significant physicists of the 19th century for his work in electricity, heat, and astronomical spectroscopy. The department chair's position will now be named for Dr. Rowland, and the university will seek additional opportunities to honor his legacy.

Michael Turner, an astrophysicist at the University of Chicago, said a gift of this scale will enhance the study of physics on a broad level.

"Astronomy and physics faculty at Johns Hopkins have been making breakthroughs that reveal our place in the universe, from the discovery of dark energy to mapping the universe today and at 380,000 years after the beginning. This extraordinary gift will enable them to continue to make the really big discoveries that only happen when you have the financial freedom to pursue edgy research. The support earmarked for young scientists is a crucial investment in the future of American leadership in science, and I can't think of a better place to be a postdoc or graduate student than Hopkinsby the way, is there an age cutoff for Miller Fellows?"

Miller is the founder and chairman of Miller Value Partners and formerly the longtime manager of the Legg Mason Capital Management Value Trust. Miller serves on the Johns Hopkins University board of trustees. He majored in economics and European History at Washington and Lee University, graduating with honors in 1972. He later served as a military intelligence officer overseas and studied philosophy at Johns Hopkins before turning to his career in investments. In 2018, he made a $75 million gift to Johns Hopkins' Department of Philosophy, believed to be by far the largest gift ever to a university philosophy program.

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Investor Bill Miller gives $50M to Johns Hopkins Department of Physics and Astronomy - The Hub at Johns Hopkins

There are places in the Universe where the laws of physics are pushed to their limits where temperatures, densities, energy, motion, and gravity are so extreme they read like an astrophysicists fever dream and sound like a science fiction plot device to everyone else.

But then, binary pulsars do actually exist.

And one particular pair of these compact bizarre objects found just a few years ago has proven to be a cosmic playground for a team of astronomers. Theyve made observations so precise theyve been able to tease out details of how the binary warps the very fabric of space itself, putting Einsteins Theory of Relativity to one of its most stringent tests ever undertaken.

Surprise: It passes, even while a couple of contender theories do not.

OK, backing up a bit: Pulsars are neutron stars, the ridiculously dense cores of massive stars after they go supernova. The outer layers of a massive star explode away, but the core collapses, compressed down from an object as big as the Sun to something literally a couple of dozen kilometers across.

These objects can be more massive than the Sun, but theyre so small their density skyrockets. A single cubic centimeter of neutron star material the size of a six-sided die can weigh 100 million tons. So yeah: dense.

When first formed, they spin rapidly and can have extremely powerful magnetic fields. Any material nearby is swept up into these fields, accelerated by them and the mind-crushingly strong gravity of the neutron star itself, and channeled down to the magnetic poles on the stars surface. The material slams into it at a respectable fraction of the speed of light, generating huge amounts of energy, focused into beams like a lighthouse. As the stars spin, these beams sweep across space, and we see them from Earth as blips of light, pulses with fantastically regular periodicity. Hence pulsars.

In 2003 astronomers discovered a pair of pulsars orbiting each other. Dubbed PSR J07373039A/B, the binary is located about 2,400 light years away in the constellation of Puppis. They orbit each other in a near-circle about 430,000 kilometers apart a little bit more than the distance of the Moon from the Earth but their over-the-top fierce gravity slings each around at a staggering 1 million kilometers per hour, completing a single orbit every 2.45 hours.

One of the two stars (pulsar A) spins once every 23 milliseconds over 40 times per second! making it what we call a millisecond pulsar, and the other (pulsar B) spins once every 2.8 seconds. Both have a mass a little over the Suns.

Put all this together and you have a phenomenal laboratory to test relativity.

A team of astronomers has used seven different radio astronomy observatories to watch this system for over 16 years, timing with exquisite precision exactly when the pulses from the two stars reach Earth. There are some obvious effects that can affect when the pulses arrive; for example, if pulsar A is on the far side of its orbit, it takes longer for the pulses to reach us due to the added distance, while the pulses from B arrive before those of A.

But theres much, much more. General Relativity is a set of rules for how things behave in extreme environments of high velocity and/or intense gravity. One effect of this is time dilation: The closer you are to a source of gravity the slower your time flows relative to someone far away. The astronomers see this in the binary: When the pulses from pulsar A, say, pass by pulsar B on their way to Earth, time for them slows down, so theres a slight delay in when we receive them, called a Shapiro delay.

Another delay occurs because of the orbital motions of the two pulsars around each other. They move so rapidly that there is an effect called relativistic beaming, which changes the angle of the light emitted ever so slightly. This too, small an effect as it is, is seen in the pulsars signal.

One of my favorite relativistic effects is due to the way the gravity of the pulsars warps spacetime, bending it like a bowling ball sitting on a bed. As the pulsars move through each other's gravity, the orientation of their orbit changes, slowly turning in space. This effect was first seen in Mercurys orbit around the Sun, and in the early 20th century was hailed as strong evidence of the correctness of Einsteins Relativity theory. Its been seen many times since, including in a star that orbits our galaxys central black hole, and is seen in the binary pulsar as well.

Theres still so much more. As the stars spin, they drag spacetime around them like a ball spinning in honey. This is called frame dragging, or more formally the Lense-Thirring effect, and it also measurably changes the pulses received from the stars.

As the stars orbit each other they emit gravitational waves, ripples in the fabric of spacetime, and this steals energy from them, shrinking their orbital size. That cant be seen directly, but as they get closer to each other they orbit more rapidly, and this changes the period of their orbit. That too has been seen in the data.

Several other subtle effects were detected as well. Clearly, this system provides some of the most stringent tests of relativity ever seen, and it passes them all.

Still, there are other theories of gravity, ones that hope to supersede relativity. We know that there are some behaviors that relativity doesnt cover, especially dealing with quantum mechanics, and so new ideas come along which potentially could modify it. These theories make predictions too, and the astronomers tested them against what they see in the binary pulsar system and find them wanting. While relativity covers their behavior extremely well, these other two ideas dont.

Thats fine! Not every idea works out, and we have to test them. Most fail. We know theres more out there than relativity and quantum theories, so we have to keep trying to figure out what it is, and we have to test these ideas against the actual Universe.

Thats what makes systems like J07373039A/B so important. They allow us to take the pulse of the Universe, so to speak, and use that information to not only develop new ideas but to test them rigorously.

Thats the point of science: To know better the truth. We dont want to fool ourselves; we want to know whats really going on out there. The rules of the Universe exist, and they are both subtle and gross. By studying the cosmos carefully, we can tease these rules out.

Continue reading here:

Binary pulsar puts Einstein to the test and he passes. Relatively speaking. - SYFY WIRE

image:A pair of stars at the start of a common envelope phase. In this artist's impression, we get a view from very close to a binary system in which two stars have just started to share the same atmosphere. The bigger star, a red giant star, has provided a huge, cool, atmosphere which only just holds together. The smaller star orbits ever faster round the stars' centre of mass, spinning on its own axis and interacting in dramatic fashion with its new surroundings. the interaction creates powerful jets that throw out gas from its poles, and a slower-moving ring of material at its equator. view more

Credit: Danielle Futselaar, artsource.nl

Unlike our Sun, most stars live with a companion. Sometimes, two come so close that one engulfs the other with far-reaching consequences. When a team of astronomers led by Chalmers University of Technology, Sweden, used the telescope Alma to study 15 unusual stars, they were surprised to find that they all recently underwent this phase. The discovery promises new insight on the sky's most dramatic phenomena and on life, death and rebirth among the stars.

Using the gigantic telescope Alma in Chile, a team of scientists led by Chalmers University of Technology studied 15 unusual stars in our galaxy, the Milky Way, the closest 5000 light years from Earth. Their measurements show that all the stars are double, and all have recently experienced a rare phase that is poorly understood, but is believed to lead to many other astronomical phenomena. Their results are published this week in the scientific journal Nature Astronomy.

By directing the antennas of Alma towards each star and measuring light from different molecules close to each star, the researchers hoped to find clues to their backstories. Nicknamed water fountains, these stars were known to astronomers because of intense light from water molecules produced by unusually dense and fast-moving gas.

Located 5000 m above sea level in Chile, the Alma telescope is sensitive to light with wavelengths around one millimetre, invisible to human eyes, but ideal for looking through the Milky Ways layers of dusty interstellar clouds towards dust-enshrouded stars.

"We were extra curious about these stars because they seem to be blowing out quantities of dust and gas into space, some in the form of jets with speeds up to 1.8 million kilometres per hour. We thought we might find out clues to how the jets were being created, but instead we found much more than that", says Theo Khouri, first author of the new study.

Stars losing up to half their total mass

The scientists used the telescope to measure signatures of carbon monoxide molecules, CO, in the light from the stars, and compared signals from different atoms (isotopes) of carbon and oxygen. Unlike its sister molecule carbon dioxide, CO2, carbon monoxide is relatively easy to discover in space, and is a favourite tool for astronomers.

"Thanks to Alma's exquisite sensitivity, we were able to detect the very faint signals from several different molecules in the gas ejected by these stars. When we looked closely at the data, we saw details that we really weren't expecting to see", says Theo Khouri.

The observations confirmed that the stars were all blowing off their outer layers.But the proportions of the different oxygen atoms in the molecules indicated that the stars were in another respect not as extreme as they had seemed, explains team member Wouter Vlemmings, astronomer at Chalmers University of Technology.

"We realised that these stars started their lives with the same mass as the Sun, or only a few times more. Now our measurements showed that they have ejected up to 50% of their total mass, just in the last few hundred years. Something really dramatic must have happened to them", he says.

A short but intimate phase

Why were such small stars come losing so much mass so quickly? The evidence all pointed to one explanation, the scientists concluded. These were all double stars, and they had all just been through a phase in which the two stars shared the same atmosphere - one star entirely embraced by the other.

"In this phase, the two stars orbit together in a sort of cocoon. This phase, which we call a "common envelope phase, is really brief, and only lasts a few hundred years. In astronomical terms, its over in the blink of an eye", says team member Daniel Tafoya of Chalmers University of Technology.

Most stars in binary systems simply orbit around a common centre of mass. These stars, however, share the same atmosphere. It can be a life-changing experience for a star, and may even lead to the stars merging completely.

Scientists believe that this sort of intimate episode can lead to some of the sky's most spectacular phenomena. Understanding how it happens could help answer some of astronomers' biggest questions about how stars live and die, Theo Khouri explains.

"What happens to cause a supernova explosion? How do black holes get close enough to collide? What's makes the beautiful and symmetric objects we call planetary nebulae? Astronomers have suspected for many years that common envelopes are part of the answers to questions like these. Now we have a new way of studying this momentous but mysterious phase", he says.

Understanding the common envelope phase will also help scientists study what will happen in the very distant future, when the Sun too will become a bigger, cooler star - a red giant - and engulf the innermost planets.

Our research will help us understand how that might happen, but it gives me another, more hopeful perspective. When these stars embrace, they send dust and gas out into space that can become the ingredients for coming generations of stars and planets, and with them the potential for new life, says Daniel Tafoya.

Since the 15 stars seem to be evolving on a human timescale, the team plan to keep monitoring them with Alma and with other radio telescopes. With the future telescopes of the SKA Observatory, they hope to study how the stars form their jets and change their surroundings. They also hope to find more if there are any.

Actually, we think the known "water fountains could be almost the only systems of their kind in the whole of our galaxy. If that's true, then these stars really are the key to understanding the strangest, most wonderful and most important process that two stars can experience in their lives together", concludes Theo Khouri.

More about the research, and about Alma

The research is published in the paper Observational identification of a sample of likely recent Common-Envelope Events in Nature Astronomy, by Theo Khouri (Chalmers), Wouter H. T. Vlemmings (Chalmers), Daniel Tafoya (Chalmers), Andrs F. Prez-Snchez (Leiden University, Netherlands), Carmen Snchez Contreras (Centro de Astrobiologa (CSIC-INTA), Spain), Jos F. Gmez (Instituto de Astrofsica de Andaluca, CSIC, Spain), Hiroshi Imai (Kagoshima University, Japan) and Raghvendra Sahai (Jet Propulsion Laboratory, California Institute of Technology, USA).

Alma (Atacama Large Millimeter/submillimeter Array) is an international astronomy facility is a partnership of ESO, the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

Chalmers and Onsala Space Observatory have been involved in Alma since its inception; receivers for the telescope are one of many contributions. Onsala Space Observatory is host to the Nordic Alma Regional Centre, which provides technical expertise to the Alma project and supports astronomers in the Nordic countries in using Alma.

For more information, contact:

Robert Cumming, Communications Officer, Onsala Space Observatory, Chalmers University of Technology,+46 31 772 5500+46 70 49 33 114robert.cumming@chalmers.se

Theo Khouri, Astronomer, Department of Space, Earth and Environment, Chalmers University of Technology+46760 958023theo.khouri@chalmers.se

Observational study

Not applicable

Observational identification of a sample of likely recent Common-Envelope Events

16-Dec-2021

Original post:

Secret embraces of stars revealed by Alma - EurekAlert

December 6, 2021

Editor's note:This story is part of a series of profiles ofnotablefall 2021 graduates.

McCall Langford was introduced to the design principles of biomimicry at a very early age. She came to appreciate the intricacies of natures complex systems, processes and forms through the work of her grandfather, Ray Anderson, founder of eco-friendly and sustainability-focused textile manufacturing company Interface. Langford was influenced by the biomimicry and sustainability thought leaders with whom her grandfather worked closely to design products inspired by the regenerative properties of the natural world. McCall Langford. Download Full Image

After receiving her bachelor of business administration in marketing from Georgia State University, she channeled her passion for equity and sustainability into the environmental nonprofit sector, serving as the director of development of One More Generation.

The pull of the natural world was strong, and she stepped away from her corporate career to immerse herself fully in nature, spending over a year camping and backpacking in the U.S. wilderness. It was there that she was able to observe just how nuanced and special the harmonious nature of the biological world truly is.

Upon returning from her adventures, Langford had solidified her lifes purpose: to not only reacquaint herself with nature, but to advocate for a global reconnection to the natural world to create a more sustainable and regenerative future. She enrolled in the College of Global Futures Master of Science in biomimicry programthrough ASU Online, and she hopes to use her experience and degree to continue to help bridge the gap between modern technology, innovation and the natural world.

Question: What was your aha moment when you realized you wanted to study the field you majored in?

Answer: I was exposed to biomimicry when I was really young through my grandfathers work. He became really active in the sustainability community through his mission at Interface. His organization worked with biomimicry consultants to create regenerative and sustainable designs.

In my undergrad, I did nonprofit development work in fundraising and donor management, later serving as the director of development of an environmental youth education and endangered species advocacy nonprofit. I also took some time away from the corporate world to backpack.

During that time, I was immersed in nature. I really started to observe the level of complexity and efficient productivity of natural processes. These natural systems are filtering water, sequestering carbon, removing air pollutants, cooling the ground, generating abundant nutrients and so on, without causing any of the issues or challenges our human designs cause. There are so many complex cooperative relationships in nature. The ecological systems surrounding us are performing all of the functional tasks that the human race is trying to accomplish, and theyre doing so much more efficiently than us.

Nature creates conditions conducive to life because its sole purpose is to continue surviving. I realized the power of natures advice, and biomimicry helps us formalize the process of asking, How does nature do this, and what can we learn from her? We could solve a lot of wicked challenges that we're experiencing at this very crucial point in human history. My big aha moment came from looking around and seeing all of this very complex solution space where these answers already exist and knowing I wanted to tap into the library of solutions the biological world is leveraging.

Q: Whats something you learned while at ASU in the classroom or otherwise that surprised you or changed your perspective?

A: It really struck me while I was in this program just how much humans are designing. Obviously we're designing buildings, infrastructure, products and a plethora of tangible things that give us modern conveniences. We are also designing so much more than that. The human race designs intangible processes and systems as well. Whether it's how you're going to spend your morning or how to engage a community, we are constantly generating new ideas for how to optimize our lives. With biomimicry, we have the opportunity to bridge innovative human design with efficient and effective nature-inspired design solutions.

Q: Why did you choose ASU?

A: In the early 90s, (her grandfather) Ray Anderson set out to identify leaders and change agents in the sustainability field to aid in the development of sustainable designs inspired by nature at Interface. Janine Benyus and Dayna Baumeister, the co-founders of Biomimicry 3.8, were among those leaders, and I followed their careers closely over the years. What I appreciated about ASU and its partnership with Biomimicry 3.8 was that the program not only stressed the importance of emulating nature in design, the ultimate goal is to create ethical and sustainable systems that work in harmony with nature. ASUs program instills emulating nature for the sake of sustainable and regenerative futures.

The holistic design thinking methodology offered at ASU guides a comprehensive approach to mimicking natural systems to establish a genuine symbiosis with the Earth. We can create conditions conducive to life, just like our natural ecosystems do, and in that process, we can re-engage a deep relationship with the natural world.

In addition to the unique opportunity to learn from leaders of the field, ASU is recognized for its prestigious and well-equipped online programming. In my eyes, there was nowhere else I wanted to go but ASU.

Q: Which professor taught you the most important lesson while at ASU?

A: Dayna Baumeister is the backbone of the biomimicry masters program. We also have a wonderful group of adjunct professors that uplift and support Daynas work while bringing additional knowledge and perspectives into the program. Its so difficult to choose just one professor who has had an impact. They have all played a massive role in the advancement of my academic career.

Q: Whats the best piece of advice youd give to those still in school?

A: My best piece of advice is to go above and beyond what the courses require of you. More specifically, identify how you can be an advocate for the work you are doing here. The master's program is built to be flexible for career professionals, designed to be accessible and achievable with this underlying implication that you can go further and customize your education and experience. Its not about the grades on your transcript, its about learning everything you can and then taking that knowledge and applying it to make the world a better place.

Q: What was your favorite spot for power studying?

A: I really don't consider this solely an online program because we're being called to go out into nature and learn from her. This program encourages us to be outside all of the time, so truly I spent most of my time out in the field, observing and learning how to view the natural world through a functional lens.

Q: What are your plans after graduation?

A: I'm formally practicing biomimicry within my regenerative design career. I'm currently working as a biomimicry consultant on a project bringing biomimetic design to an 18-mile stretch of testbed highway that's been deemed an innovation lab for regenerative design. The innovation lab initiative is showing interest in pulling in bio-inspired design to improve the regenerative qualities of our nations transportation systems. After graduation I'm going to continue leveraging biomimetic design to get us closer to the harmonious place that I know we can arrive.

Q: If someone gave you $40 million to solve one problem on our planet, what would you tackle?

A: The School of Complex Adaptive Systems focuses on developing frameworks to guide the design of our systems, while in a highly technical way, also incorporating these frameworks into social and conceptual designs. To do both, you have to have a culture shift, so Id love to put that towards encouraging people to invest in biomimetic solutions by showing them how regeneration will improve their conditions. I would invest the $40 million into demonstrating the value of funding and implementing regenerative and efficient systems inspired by the natural world in lieu of a lot of the current maladaptive solutions.

Were getting there. Over the past decade weve seen a massive culture shift towards a more equitable and inclusive social mentality. We definitely have to address the economic and social perspectives before we can see the massive complex systems change necessary to solve these wicked problems.

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Path to PhD started with a small planetarium and an intro astronomy course - ASU Now

Beta Crucis is represented in the flags of Australia, Brazil, New Zealand, Papua New Guinea and Samoa.

Beta Crucis. Image credit: Naskies at en.wikipedia / CC BY-SA 3.0.

Beta Crucis is a triple star system located at a distance of 280 light-years from the Earth.

Also known as HD 111123, HIC 62434, Becrux and Mimosa, it is the second-brightest object in the constellation of Crux and the 20th brightest star in the night sky.

The primary star in the system, beta Crucis A, is a beta Cephei variable star with rapid brightness changes.

The secondary, beta Crucis B, is a main sequence star with a stellar class of B2.

And the third companion is a low mass, pre-main sequence star.

To crack the age and mass of beta Crucis A, Dr. Daniel Cotton from the Australian National University and Monterey Institute for Research in Astronomy and his colleagues combined asteroseismology, the study of a stars regular movements, with polarimetry, the measurement of the orientation of light waves.

Asteroseismology relies on seismic waves bouncing around the interior of a star and producing measurable changes in its light, they explained.

Probing the interiors of heavy stars that will later explode as supernovae has traditionally been difficult.

In the study, the authors analyzed data from NASAs WIRE and TESS satellites, high-resolution spectroscopic data from ESO, and polarimetric data from Siding Spring Observatory and Western Sydney Universitys Penrith Observatory.

We wanted to investigate an old idea, Dr. Cotton said.

It was predicted in 1979 that polarimetry had the potential to measure the interiors of massive stars, but its not been possible until now.

The size of the effect is quite small, added Professor Jeremy Bailey, an astronomer at the University of New South Wales.

We needed the worlds best precision of the polarimeter we designed and built.

The team found beta Crucis A to be approximately 14.5 times as massive as the Sun and around 11 million years old, making it the heaviest star with an age determined from asteroseismology ever.

Analyzing the three types of long-term data together allowed us to identify Mimosas dominant mode geometries, said Professor Derek Buzasi, an astronomer at Florida Gulf Coast University.

This opened the road to weighing and age-dating the star using seismic methods.

This polarimetric study of Mimosa opens a new avenue for asteroseismology of bright massive stars, added Professor Conny Aerts, an astronomer with the Institute of Astronomy at KU Leuven, Radboud University Nijmegen, and the Max Planck Institute for Astronomy.

While these stars are the most productive chemical factories of our Galaxy, they are so far the least analyzed asteroseismically, given the degree of difficulty of such studies. The heroic efforts by the Australian polarimetrists are to be admired.

The teams paper was published in the journal Nature Astronomy.

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D.V. Cotton et al. Polarimetric detection of non-radial oscillation modes in the Cephei star Crucis. Nat Astron, published online December 6, 2021; doi: 10.1038/s41550-021-01531-9

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Astronomers Measure Mass and Age of Beta Crucis A - Sci-News.com

Close-up and wide views of the nearest pair of supermassive black holes.

Scientists have spotted a pair of the most powerful monsters known to humans, and this destructive duo is closer to our planet than any ever seen before.

Fortunately, the couple of supermassive black holes discovered by astronomers using the Very Large Telescope in Chile are still 89 million light years away from us in the galaxy NGC 7727. That's plenty far enough for humanity to be able to continue to sleep well at night for the rest of our existence without being kept up by the prospect that this terrible team is coming to swallow everything we've ever known.

Unlock the biggest mysteries of our planet and beyond with the CNET Science newsletter. Delivered Mondays.

But while it's a comfortable distance, it's much closer than the previous record for a supermassive black hole pair, which is 470 million light years distant.

Karina Voggel, an astronomer at the Strasbourg Observatory in France, explains in a statement that these tumultuous twosomes form when huge galaxies merge and the supermassive black hole at the center of each set a course for collision.

"It is the first time we find two supermassive black holes that are this close to each other, less than half the separation of the previous record holder."

That separation is more than it appears, though, at 1,600 light years.

Voggel is also lead author of apaperdetailing the new discovery published online Tuesday in the journal Astronomy & Astrophysics.

Remarkably, when the two already supermassive black holes eventually do collide, the will create an even bigger nightmare void.

"The small separation and velocity of the two black holes indicate that they will merge into one monster black hole, probably within the next 250 million years," adds co-author Holger Baumgardt from the University of Queensland in Australia.

The researchers say they now expect to find even more such cosmic colossuses in deep space.

"Our finding implies that there might be many more of these relics of galaxy mergers out there and they may contain many hidden massive black holes that still wait to be found," says Voggel. "It could increase the total number of supermassive black holes known in the local Universe by 30 percent."

Some may be even closer to Earth, which should be okay, so long as we measure the distance in millions of light years.

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Astronomers spot supermassive black hole duo that's the closest to Earth yet - CNET

Theres something strange about the dwarf galaxies around the Milky Way.

These smaller galaxies orbit our own, but many of their orbits align along what astronomers term the vast polar structure: a pancake-shaped plane that intersects our own crepe-thin galaxy. Out of the dozens of known satellites in the Milky Ways retinue, about half of them, maybe even more, belong to this structure, dotting the plane like raisins in the pancake. Whats more this pancake rotates, the blueberries whirling around the Milky Way in the same direction.

This alignment has puzzled astronomers since the first hints of it appeared in the 1970s. Cosmological simulations dont generally predict this effect. Some researchers have even wondered if the problem is with our understanding of dark matter or of gravity itself.

In a paper posted to the astronomy preprint arXiv, Nicols Garavito Camargo (University of Arizona) and colleagues suggest the focus ought to be on the biggest of all the little fish: the Large Magellanic Cloud (LMC).

The LMC is a massive dwarf, with at least a tenth the mass of the Milky Way. Its swinging around our galaxy for the first time on a trajectory that aligns with the vast polar structure, and it may have brought a half dozen smaller galaxies in with it. That cant be a coincidence, right? Astronomers have thought so, too, and several have suggested that the LMC has somehow inspired the mysterious polar structure.

In fact, earlier this year, Jenna Samuel (now at University of Texas, Austin) and colleagues made this case: Samuels led simulations to demonstrate that dwarf galaxies tend to align along cosmic pancakes and stay that way, at least for a while when theres a massive dwarf like the LMC in the mix.

The question is how: The LMC and its retinue are only a few of the Milky Ways many satellites, so it and its attendants cant account for the plane simply by falling in. Garavito Camargo and colleagues describe how the LMC could have affected the orbits of the other galaxies.

In short, the dwarf galaxy is throwing its weight around, affecting the Milky Way, its dark matter halo, and its satellites, all via the simple force of gravity. Not only does the dwarf pull on the other satellite galaxies ahead of it in its orbit, it also draws the material behind it into a wake. In addition, the researchers realized, they would need to account for their own place in the galaxy.

As it falls in, the LMC has pulled the Milky Way off-center. Our galaxy is enormous, though, and the shift in center of mass has taken time to travel outward. While the inner regions of the galaxy and its halo are already orbiting the new center of mass, the outer regions havent gotten the memo yet. So, from our perch in the inner galaxy, we see the outer regions rotate.

Were actually in a moving car, when we thought we were just sitting still, explains coauthor Gurtina Besla (University of Arizona). You see all these things move by you and you think theyre moving at some speed, but in fact were moving along with it and theyre actually moving slightly slower. In effect, when we see the satellite galaxies moving together in concert, some of that is simply the effect of our own motion something that we hadnt considered before.

Garavito Camargo, Besla, and colleagues combined all of these effects in a simulation of the LMCMilky Way encounter, confirming that the LMCs infall is capable of reshaping the orbits of numerous objects around the Milky Way.

Even taking all these effects together, though, they still might not fully explain the strange alignment of Milky Way satellites. Then again, they dont have to: After all, cosmological simulations do create planes of satellites, just not ones as organized as the one around the Milky Way.

The idea is that, after correcting for all these effects, the remaining plane may better resemble the structures predicted in cosmological simulations, Garavito Camargo says. All this together can create something thats kind-of weird and statistically more improbable than what you might find in a generic cosmological simulation.

The new work offers a fresh approach and one that is a very thorough and convincing piece of research, which naturally got me and others working on this issue very excited, says Marcel Pawlowski (Leibniz Institute for Astrophysics Potsdam), who wasnt involved in the new study. He maintains, however, that theres still work to be done to understand the structures origin.

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How Our Largest Dwarf Galaxy Keeps the Others In Line - SkyandTelescope.com

In a first, astronomers may have seen light from the merger of two black holes, providing opportunities to learn about these mysterious dark objects.

This artist's concept shows a supermassive black hole surrounded by a disk of gas. Embedded in this disk are two smaller black holes that may have merged together to form a new black hole.

When two black holes spiral around each other and ultimately collide, they send out gravitational waves - ripples in space and time that can be detected with extremely sensitive instruments on Earth. Since black holes and black hole mergers are completely dark, these events are invisible to telescopes and other light-detecting instruments used by astronomers. However, theorists have come up with ideas about how a black hole merger could produce a light signal by causing nearby material to radiate.

Now, scientists using Caltech's Zwicky Transient Facility (ZTF) located at Palomar Observatory near San Diego may have spotted what could be just such a scenario. If confirmed, it would be the first known light flare from a pair of colliding black holes.

The merger was identified on May 21, 2019, by two gravitational wave detectors the National Science Foundation's Laser Interferometer Gravitational-wave Observatory, or LIGO,and the European Virgo detector in an event called GW190521g. That detection allowed the ZTF scientists to look for light signals from the location where the gravitational wave signal originated. These gravitational wave detectors have also spotted mergers between dense cosmic objects called neutron stars, and astronomers have identified light emissions from those collisions.

Learn more:What Is a Black Hole?

Black Hole Image Makes History; NASA Telescopes Coordinated Observations

Image Credit:Caltech/R. Hurt (IPAC)

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Astronomy Picture Of The Day: What in the world (or galaxy), is that? - WDRB

The best astronomy, space and stargazing books for Christmas 2021.

Did you look up in lockdown? Millions did and have since developed a fascination with the night sky, but stargazing and astronomy isnt easy for beginners. The best way to get more from the night sky and to delve deeper into astronomy is to learn from the experts, many of whom prepared excellent, easy to read books during the various lockdowns.

Here are some of the finest new space, stargazing and astronomy books to delve into this winteror to treat someone else to this Christmas.

The Backyard Astronomer's Guide by Terence Dickinson and Alan Dyer

By Terence Dickinson and Alan Dyer

How do go from being a casual stargazer to an accomplished amateur astronomer? You buy this book, thats how. An exhaustive large-format hardback book full of diagrams and color photos, this sky bible first published in 1991 here gets a fresh edition.

A product of the lockdownas many of the books here arethis new version now runs to 416 pages, includes more observing guidance, and has fresh advice on the very latest telescopes, binoculars and smartphones.

As someone who travels to the southern hemisphere I also appreciated the lack of northern hemisphere bias, which blights so many complete guides to the night sky, and the coverage of both lunar and solar eclipses.

Northern Lights: The Definitive Guide To Auroras by Tom Kerss

By Tom Kerss

Have you ever seen the Northern Lights? Would you know what to do if they appeared in front of you? Host of the Star Signs weekly stargazing podcast and founder of Stargazing.London, Tom Kerss guide to the Northern Lights goes way deeper than you might expect.

While packed with basic, practical information about how to see and photograph the Northern Lights this book also includes a wonderful overview of aurora through the centuries. Inside are some gems about how our planets magnetosphere works to just how and why Captain Cook witnessed the aurora in 1770 while sailing south of the equator.

In youre headed to the Arctic Circle then this guide will help to get the most out of your trip.

Atlas Of Solar Eclipses

By Michael Zeiler and Michael E. Bakich (GreatAmericanEclipse.com)

Although originally launched in 2020, that years total solar eclipse was poorly attended due to COVID-19. So if youre getting your travel legs back and thinking about taking new adventures check out this excellent, authoritative and entertaining reference book of all the solar eclipses partial, annular (ring of fire) and the hallowed totalthat will grace our planet through 2045 ... which is going to be abigone for North America.

'The Secret World of Stargazing' by Adrian West.

By Adrian West @VirtualAstro

There are billions of humans on this planet, and only a tiny fraction of us understand and enjoy the night sky. So says Adrian West, better known as @VirtualAstro on Twitter, on the exclusive yet increasingly inclusive hobby thats currently on-trend.

In this accessible and feel-good stargazing guide he majors on how looking up at the night sky is good for mental well-being. A book born out of the pandemic lockdowns, its 14 chapters cover everything from getting started to what to look at each season. It also touches on an obsession of the author on Twitterbright passes of satellites such as the International Space Station (ISS).

Written from the heart but with expert tips, The Secret World of Stargazing acts as a succinct and simple to understand manual for any accidental stargazers who picked up the habit during 2020 and now want to take the next step and learn to navigate and to know the night sky.

Natalie Starkey's new book, Fire and Ice: The Volcanoes of the Solar System.

By Natalie Starkey

Space volcanoes are fascinating. Theyre how a planetary body cools itself down, releasing excess heat into space. For geologists, volcanoes on a planet or moon is evidence that a world is activealive!

But spewing ice? Volcanoes do that? They do on Triton, a moon of Neptune, and on Enceladus at Saturn. Weird Titan at Saturn may even have ice volcanoes that pump out methane.

The first to examine the extra-terrestrial volcanoes of our Solar System, Natalie Starkeys latest is an explosive read in more ways than one that will give you a new perspective on both the planets closest to us and of the darker corners of our Solar System.

Philip's Month-by-Month Stargazing 2022 by Nigel Henbest

By Nigel Henbest

If youre going to be a good stargazer you need to know exactly whats going happen, when, and where youll be able to see it from where you live. You can do a lot of that online, but a much easier way is to read this short, accessible guide to the night sky that for the first time includes information on basic astrophotography and a dark sky map of Britain and Ireland.

So whats going to happen above us in 2022? Highlights include a fabulous conjunction of Venus and Jupiter, a total eclipse of the Moon and a rare occultation of a bright Mars by the Moon.

With each month treated to a summary of highlights, a calendar of events and a handy skychart, this timely guide from Dr. Nigel Henbestwho had been writing the annual Philips guide with the late Dr. Heather Couper for many yearsis an excellent way to prepare your eyes for clear skies.

Wishing you clear skies and wide eyes.

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Can You Read The Night Sky? Six Of The Best New Space, Stargazing And Astronomy Books For Christmas 2021 - Forbes

Nov 26th 2021

WALT WHITMAN, the greatest male American poet of the 19th century, and Billy Bragg, the self-proclaimed big-nosed bard of Barking, may not at first seem to have much in common. But both have inveighed against interference with the solace, wonder and communion offered by the unspoiled and unmediated night sky. The protagonist of Whitmans When I heard the learn'd astronomer walks out of an alienating lecture on the science of stars and planets. He wanders off by himself

The lovelorn youth of Mr Braggs debut single, A New England, laments the fact that he

Today it is the learnd astronomers who wish someone would care, because they are facing space hardware in unprecedented profusion. The idea of reaching billions of people in places hard to wire into the internet has led to a series of schemes seeking to provide wireless broadband from the sky, and it is in the nature of such schemes that they require inordinate numbers of fairly low-flying satellites. SpaceX, the leader in this new market, already has a shell of 1,584 satellites circling the Earth. Within a few years it wants to have enough shells to make use of 40,000.

Others have plans at least as ambitious. In a decades time thousands of swift artificial stars may be racing through the dawn and dusk, and a significant part of the nights in between. They will probably not, for the most part, be noticeable to the naked eye. But for those observing the cosmos with sophisticated instruments, they will be a substantial obstacle.

Layering the outermost reaches of the atmosphere with a hardwaresphere is a signal achievement. Human enterprise can now mass-produce sophisticated equipment that functions in the harshest environments and lift it to the heavens in bulk. In so doing companies can bring fully connected modernity to people everywhere. Meanwhile smaller constellations will monitor the Earth more closely, more constantly and more fully than ever before, tracking its changes and helping its inhabitants understand what they are doing from a Gods eye point of view.

But all expansions bring externalities, and the number of such satellites is becoming an issue in many ways. It seems bizarre to think of low-Earth orbita quadrillion cubic kilometres of empty space, roughly as large a volume as that of the planet which sits at its centreas being crowded by a population of satellites unlikely to number more than a mere million. But in terms of collision-risk and the sight of the stars that is becoming the case.

Collisions are the deepest concern. They do not just wreck the satellites involved: the debris they create puts other satellites at higher risk, too. There are legitimate fears that after a threshold number of collisions a chain reaction will take off that makes whole classes of orbit unusable. That is why anti-satellite-missile tests like the one conducted by Russia a couple of weeks ago are so reprehensible. The world urgently needs to deal with this, and the related issue of what to do with satellites that are defective or have reached the end of their lives.

One problem is that it is cheaper to let others tend to the orbital commons than pitch in yourself. Another is that anti-satellite weapons used in earnest might well overturn the apple cart. But in the normal run of things, the interests of satellite operators are generally aligned when it comes to keeping low Earth orbit clear enough to be useful. Get the regulations, norms and incentives right and technologies that allow orbits to be cleaned up could find buyers.

In the case of the astronomers clear view of the cosmos things are less straightforward. If humankind has a common cultural heritage of any sort at all, the night sky must surely form part of it. But no authority is in a position to protect it as such, and compensating astronomersor for that matter humans at largefor the satellites that get in their way feels more like a piece of satire than a policy proposal. The interests of astronomers and satellite-owners are incommensurate, and there is no overarching authority to decide between them. So facts in the sky are likely to count for everything.

The two sides are trying to minimise the problem. Astronomers are looking at new ways to observe; satellite designers at ways of making their creations less bright. But each side could do more.

Professional astronomers need to reconsider the degree to which their field, and particularly the space-based bits of it, is dominated by the most expensive telescopes money can buy. Launching things into space is cheaper than it used to be, and it is set to get cheaper still; satellite technology, as the constellations show, has come on in leaps and bounds.

That makes it time for a serious attempt to break the interlocking feedback cycles through which space-science missions, having become expensive, need to have any associated risks minimised, which makes them more expensive. That leads them to crowd out smaller missions, which means they need to serve more parts of the community which, again, makes them more expensive. That means their budget has to be spread over a longer period of time; that too makes them more expensive.

Those are the sort of dynamics which produce a $10bn marvel like the James Webb Space Telescope, a scientific instrument which has cost as much as a nuclear aircraft-carrier. Is it better to spend such a sum on a unique capability for observing the cosmos than on yet another war machine? Quite possibly. Must new views of space cost quite that much? Very probably not.

Finding ways to do astronomy more cheaply in space would allow professional observations to be made above the fray, as it were. But the new satellite constellations would still frustrate amateurs, and quite possibly those who simply stop in their tracks on a clear night to look up and wonder. Here the satellite companies can do something to make amends. For most people satellites are not the only or greatest constraint on the observability of the universe. Street lighting and other forms of light pollution do more harm.

Satellite companies should encourage and subsidise the local initiatives to reduce light pollution that can be found all over the world. If so, they might find that such deeds might buy them good will. And if making the sky easier to appreciate in all its glory also means that people become more aware of your satellites, they may well be more inclined to forgive you for it.

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Why the nights grow less dark, and what to do about it - The Economist