Until now, all the pictures of the sun have been straight-on head shots. Soon, scientists will be getting aprofile.

NASA and the European Space Agency are set to launch a joint mission on Sunday to provide the first-ever look at the suns poles. Previous images have all been taken from approximately the same angle, roughly in line with the starsequator.

Scientists are hesitant to guess what the elusive poles of the star might look like. I hate to speculate, says Holly Gilbert, the NASA project scientist for themission.

Were constantly taken by these discoveries where we thought we knew what something would be before we measured it for the first time, says David McComas, an astrophysics professor at Princeton University. And then we go like, Oh, geez, thats really different than we expected. So, I think we want to keep an open mind aboutthat.

After the NASA/ESA probe called Solar Orbiter takes off from Floridas Cape Canaveral, itll use Venus and Earths gravity to propel itself outside that equatorial plane where all the planets in our solar system orbit the sun. Orbiter eventually will be able to look down onto the poles of thesun.

There are many reasons why scientists want to know more about the suns poles. They think the poles might be driving some important aspects of space weather throughout the solar system, which can impact spacecraft and even humans on Earth. It has real world effects on our satellites, our GPS, our power grid and things like that, McComassays.

As we get more and more technologically advanced, the more susceptible we are to space weather and the more important it becomes to be able to forecast and hopefully ultimately predict, Gilbert says. The data that Orbiter collects could eventually help build models forecasting spaceweather.

The mission will map the suns magnetic fields from the poles. Scientists think these fields have a complicated relationship with whats happening inside thesun.

Since the 1800s, scientists have noticed that the sun goes through cycles between points of relative calm and high activity. The active times are associated with a lot of sunspots, a lot of flares, and solar storms, Gilbert says. These cycles happen roughly every 11years.

Scientists dont fully understand what causes these cycles. But theyve noticed that they line up with major changes in the suns magnetic field. One pole is positive and one is negative and every 11 years, the poles swap and have the oppositecharge.

Gilbert says the changing polarity is likely because of activity inside the sun. Its a very complicated, rotating ball of gas and that causes the magnetic fields to get all tangled up. The fields store magnetic energy, which can escape in the form of solar storms when the fields get snarled. Its a chaotic process that can result in the poles switchingpolarity.

It would be useful for scientists to better understand when the biggest flares are going to happen, in order to protect satellites and other spacecraft. Even though we have ideas about how many sunspots and how many storms and how often they might occur, we cant really predict how strong theyre going to be, Gilbertsays.

The Solar Orbiter will also be able to collaborate with another probe circling the sun. NASAs Parker Solar Probe launched in 2018 and will eventually come within 4 million miles of the suns surface far closer than this new mission. It will move through the suns corona, a super-hot aura of gases around the star, and gather data on its magnetic fields and energetic particles, as NPRs Nell Greenfieldboyce has reported.

At certain points, the Solar Orbiter will be positioned along the same magnetic field line as the Parker probe. Gilbert says this means theyll be able to measure particles at two different times once at Parker and then once again when they reach the Solar Orbiter. Were going to have a nice picture of evolution of some of these particles and how that flow is changing as its moving away from the sun, shesays.

McComas, who is involved in the Parker mission, says hes excited to be able to look at the solar wind from two different latitudes at that same time. That solar wind blasts the suns magnetic field in all directions, which can create the space weather bursts that interfere with satellites andGPS.

We almost always measure it from this one perspective in the equatorial plane, he says. Having these measurements from two perspectives will allow them to determine whether the perspective that weve always known is representative or as he explains, maybe theyll say, Gee, its really different when you get to be, you know, 30 degreeshigher.

Its worth noting that scientists are also getting unique views of the sun from the National Science Foundations Daniel K. Inouye Solar Telescope. Last month, the foundation released unprecedented, mesmerizing photos of the suns surface.

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Polar Express: New Spacecraft Will Explore Elusive Parts Of The Sun - OPB News

Indiana Universitys newly dedicated Big Red 200, its $9.6 million artificial intelligence supercomputer,

IU dedicated Big Red 200 as part of its Day of Commemoration Bicentennial event Jan. 20. It is the first in a revolutionary new Cray, Inc. line of exascale supercomputers that the Hewlett Packard Enterprise company has branded Shasta.

Department of Energy laboratories plan to install larger Shasta iterations in the coming years as part of an Exascale Computing Project to develop the worlds fastest supercomputers, with exascale speeds exceeding 10 to the eighteenth power calculations per second.

To illustrate the speed of what is now Indianas fastest supercomputer, IU said Big Red can perform the same number of calculations in 1 second that everyone in the state could perform together over 28 years if they could each perform one calculation per second nonstop during that period.

I am excited about utilizing the AI capabilities of Big Red 200 to accelerate the research programs in the Department of Medical and Molecular Genetics at the IU School of Medicine, Tatiana Foroud, the departments chairwoman, said in an announcement.

I believe this new AI-capable supercomputer will enable breakthrough discoveries across a broad range of research areas, including neurodegeneration and the study of Alzheimers disease, she said.

Importantly, Big Red 200 will be an essential resource for the Precision Health Initiative, one of the Indiana University Grand Challenges, which is designed to enhance the prevention, treatment and health outcomes of human diseases through a more precise analysis of the genetic, developmental, behavioral and environmental factors that shape an individuals health.

In addition to medicine, Big Red will support IU advanced research in artificial intelligence, machine learning and data analytics.

The 200 was added to Big Reds name to commemorate IUs Bicentennial. The new supercomputer is replacing a supercomputer that is becoming obsolete, which was installed in 2013 as the deep learning revolution was gaining steam.

PFW adds astronomy concentration

The physics department at Purdue University Fort Wayne plans to start offering northeast Indianas only concentration in astronomy and astrophysics this coming fall.

Students completing the four-year program will graduate with a bachelors degree in physics with an astronomy concentration.

In addition to astrophysics, it will include classes in planetary astronomy and beginning and advanced stellar astronomy and cosmology.

The program also will offer optics and optics laboratory special sections as well as instrumentation-related classes such as electronics for scientists, instrumentation and spectroscopy or atomic and molecular physics.

Students in the program also will learn how a telescope works and how to build and use one.

The students who choose to follow the astrophysicist path will have a skill set in project management and will be able to design an instrument package for a satellite. Mark Masters, professor and chair of the physics department, said in an announcement.

Much like physics students, the astronomy students can apply their experimental, data analysis, and other skills to many different fields, he said.

They are problem solvers. They will be able to have careers that range from the financial industry, programming, engineers, technicians, and astronomers.

PFWs fall 2020 class schedule will be posted online by the end of February with staggered registration starting in March.

Elevate Nexus continues pitch competitions

Entrepreneurs in the region had until Feb. 3 to apply for participation in the second Elevate Nexus Regional Pitch Competitions.

Elevate Ventures planned to select finalists Feb. 4 in order to invite them to participate in their regions version of the business plan pitch competition.

The Northern Regions version was scheduled for Feb. 25 at Innovation Park at Notre Dame, 1400 E. Angela Blvd. in South Bend.

Indianapolis-based Elevate Ventures started the Elevate Nexus program last year to help colleges and universities in the state that did not already have them to initiate the investment pitch competitions.

The first of Elevates regional pitch competitions leading to a statewide competition took place last October.

Of 75 applicants, 67 finalists were invited to compete in that contest, which provided the entrepreneurs 10 minutes each to convince a panel of regional judges their companies would be the most likely to provide the best returns on seed and pre-seed investments.

The competition awarded pre-seed investments of $20,000 each to nine businesses and seed investments of $80,000 each to six businesses, including Pierceton-based CoolCorp Inc. and Warsaw-based Eclipse Orthopaedics.

In addition to the funding, competition winners became Elevate portfolio companies and gained access to its network of advisers and resources, the announcement said.

The winners also were invited to pitch to judges in a similar, statewide competition with $40,000 pre-seed and $100,000 seed investments. That event will take place April 14 as part of Elevates annual Kinetic conference.

Abbott honors Team Stroy at Statehouse

State Rep. David Abbott, R-Rome City, recently honored Fort Wayne native Morgan Malm at the Statehouse along with other winners of Purdue Universitys 2019 Student Soybean Product Innovation Competition.

Funded by the Indiana Soybean Alliance through a soybean checkoff program, Abbott said the competition challenges students to create a new industrial product using soybeans.

Malm was pursuing a food science doctorate at Purdue last year when she and classmates Natalie Stephenson and Ruth Zhong placed first for their development of a biodegradable, environmentally friendly straw they dubbed Stroy.

Malm developed a structure for the straw of soy protein film, and then because it was water soluble, she searched the candy and pharmaceutical industries for an existing coating that could protect it for several hours after it came in contact with water.

The alliance had provided $300 to develop the prototype. Archer Daniels Midland had donated the soy protein for it, and the team bought two other ingredients for it on Amazon.

Members of Team Stroy received a $20,000 prize for their months-long effort. The innovation the group showed is nothing short of remarkable, Abbott said in a news release.

This soy-based straw looks and feels almost exactly like a plastic straw, while being completely bio-degradable. Soybeans are used for so many things in society, and this product could potentially boost Indianas soybean production.

The trio hopes to market the Stroy to the restaurant, fast-food chain and coffee and snack shop industry.

Its feasible this invention could affect the states agricultural and economic growth as soybean production could rise, Abbott said.

A group of soybean farmers, marketing specialists and scientists judging the contest at Purdue appreciated the fact that the prototype for the biodegradable, soy-based Stroy offers the material consistency of a plastic straw but breaks down in a matter of days if it is thrown away

Col. Stohler to keynote NIBCC luncheon

Col. Michael Stohler, commander of the 122nd Fighter Wing in Fort Wayne, will keynote the first luncheon of the decade for the Northeast Indiana Base Community Council.

His presentation entitled Your Citizen Airmen will provide an overview of the 122nd and what it does for the country and community. The luncheon will take place at 11:30 a.m. Feb. 12 at the Parkview Mirro Center, 10622 Parkview Plaza Drive in Fort Wayne.

Stohler has commanded the 122nd since April 2018 when its previous commander, Patrick Renwick, was promoted to brigadier general from colonel and began serving as a senior adviser to the adjutant general of the Indiana Air National Guard in Indianapolis.

With more than 4,100 hours in the F-16 and A-10 fighter aircraft, the command pilot has logged 833 hours during 161 combat sorties supporting operations Southern Watch, Iraqi Freedom, Enduring Freedom and Inherent Resolve.

During his Inherent Resolve service, he became the first commander of the reactivated Red Tails of the 332nd Air Expeditionary Group.

Stohler served as the Indiana Air Guards state director of operations at its Joint Forces Headquarters in Indianapolis prior to leading the 122nd.

He works as a commercial pilot out of Fort Wayne International Airport when not serving in the Air National Guard.

The cost of the luncheon is $25 with a $5 discount for NIBCC members or members of the military community. Gold Tables, which seat eight, are available for $500. More information on the event is available at http://www.nibcc.org.

Hendrix to speak on state 5G plans

Sean Hendrix, director of emerging technology partnerships for Purdue Research Foundation and managing director for the Indiana 5G Zone, will provide the program for the next local Networking Information Technology Association meeting.

His presentation on The 5th Generation Mobile Network will take place at 11:30 a.m. Feb. 7 at Kettler Hall, Room G46, at Purdue University Fort Wayne, 2101 Coliseum Blvd. E.

5G promises to be transformative from new smartphone uses, automated vehicles, and the Internet of Things to remote healthcare, augmented and virtual reality, industrial automation and more the innovations of the future will be built on 5G, a meeting announcement said.

However, defining what 5G is, developing an understanding of how physical industries will be digitized, and understanding where Indiana fits in the overall picture presents both opportunities and challenges. We will explore these questions in an effort to develop the roadmap forward.

The local NITA has changed its meeting day from the first Thursday of the month to the first Friday.

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Department of Energy to use IU's Big Red 200 supercomputer; Purdue University Fort Wayne offering astronomy concentration - FW Business

Models suggest black holes can stretch devoured stars into long streamers.

By Daniel CleryJan. 28, 2020 , 5:05 PM

At the center of nearly every galaxy lies a monster, a giant black hole millions or even billions of times heavier than the Sun. Some, known as quasars or active galactic nuclei, shine brightly from across the universe as they continuously devour surrounding gas. But most are dormant, lurking invisibly for thousands of yearsuntil a star passes too close and is ripped to shreds. That triggers a monthslong tidal disruption event (TDE), which can shine as brightly as a supernova.

Until a few years ago, astronomers had spotted only a handful of TDEs. But now, a new generation of wide-field surveys is catching more of them soon after they startyielding new insights into the violent events and the hidden population of black holes that drives them.

Were still in the trenches, trying to understand the physical mechanisms powering these emissions, says Suvi Gezari of the University of Maryland, College Park. Earlier this month at the annual meeting of the American Astronomical Society in Honolulu, Gezari presented an analysis of 39 TDEs: 22 from recent years and 17 detected in the first 18 months of operation of the Zwicky Transient Facility (ZTF), a 1.2-meter survey telescope in California.

In the standard TDE picture, the gravity of the black hole shreds an approaching star into strands like spaghetti. The black hole immediately swallows half the stars matter while the rest arcs away in long streamers. These rapidly fall back and settle into an accretion disk that steadily feeds material into the black hole, growing so hot that it emits copious x-rays.

An x-ray mapping satellite spotted the first TDEs in the 1990s. Now, optical surveys like the ZTF are picking up the fast-changing events and capturing telltale details of the visible glow. They are also alerting other observatories, such as NASAs Swift telescope, to make follow-up observations at ultraviolet and x-ray wavelengths.

The fingerprints of certain gases in the spectra of the visible light can reveal what kind of star went down the black holes maw. Gezari and her colleagues found that the TDE spectra fell into three classes, dominated by hydrogen, helium, or a mixture of gases. Hydrogen likely signals large, young stars, whereas helium events could point to the cores of older stars whose hydrogen shells were stripped awayperhaps by an earlier brush with the black hole. She says the proportions reveal something about the populations of stars at the very centers of galaxies, at distances from Earth that would otherwise be impossible to probe.

If astronomers could turn the light into a reading of how quickly material is being sucked in, they might be able to determine a black holes masssomething usually estimated crudely by measuring the size of its galaxy. For that, however, We need to understand the astrophysics of the process with greater clarity, says Tsvi Piran of the Hebrew University of Jerusalem. For a few TDEs, astronomers have been able to compare the rise and fall of the visible glow with x-ray measurements made from spaceand puzzlingly, the two dont match. The x-rays often flare irregularly, appear late, or are absent altogether.

The x-rays could be steady but obscured by a cloud of gas, hundreds of times bigger than the black hole, that forms from a backlog of material, says Kate Alexander of the Harvard-Smithsonian Center for Astrophysics. Its like the black hole gets indigestion because it eats too much too fast. Piran thinks its more likely that the x-rays are generated in bursts, as clumps of matter fall into the black hole. Either way, astronomers arent ready to glean a black holes mass from a TDEs brilliance.

Theory does suggest black holes can become too massive to trigger TDEs. Above a mass of 100 million suns, black holes should swallow stars whole rather than tearing them apart as they approach. So far, all of the growing number of TDEs come from smaller galaxies, suggesting the limit is real.

TDEs could even provide a window into a more elusive black hole characteristic: its spin. Dheeraj Pasham of the Massachusetts Institute of Technology has studied the soft x-ray emissions of three TDEs that pulse in semiregular beats. He says similar, higher frequency beats have been observed coming from smaller, stellar-mass black holes, and he suspects the pulsing reflects the black holes spin. Constraints on this property could help solve an enduring mystery: whether giant black holes form by slowly accreting stellar matter over their lifetimea process expected to produce a fast spinor by merging with the giant black holes from other galactic cores, which would result in a slower spin. An x-ray survey of many TDEs could reveal which process dominates.

With the tally of captured TDEs growing fast, and hundreds or even thousands of discoveries per year expected from new surveys, researchers are hopeful that the events will answer more questions. My dream is for TDEs to be some kind of ruler or scale for black hole mass, Gezari says. Were not there yet but were getting closer.

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Black holes caught in the act of swallowing stars - Science Magazine

Dr. V. Venkatraman Krishnan, et al.

A team of astrophysicists from around the world has been following an unusual pair of spinning stars for almost 20 years, and now they say the binary system is persuasive evidence of frame dragging. In a new paper in Science, the researchers say the white dwarf and neutron star that spin extremely fast together form an edge case to demonstrate relativity.

Relativistic frame dragging is an offshoot of Einsteins general theory of relativitythe idea that individual objects in the curvature of spacetime cause changes within that spacetimewhere scientists observe that objects with energy can cause spacetime to bend and bunch in order to absorb the extra energy.

In this case, a special binary system is so forceful and sped up that the effects are more visible to scientists. The system, named PSR J1141-6545, is made of two stars: One is a white dwarf, the size of the Earth but 300,000 times its density; the other is a neutron star which, while only 20 kilometres in diameter, is about 100 billion times the density of the Earth, the press release says.

Something so tiny and extremely dense, especially in a conjoined spin with a second star that itself would be considered quite small and quite dense in any other circumstance, ends up spinning so fast that it bends and wobbles. The tiny neutron star is a pulsar, meaning it emits a steady beam of light that can be tracked as it spins, like when the suns reflection off a metal object points directly in your eyes as you walk past.

Monitoring the frequency of these spinning pulses lets scientists begin to make an overall picture of how the neutron star is orbiting. All pulsars are useful for research into astrophysics because of the way their size and density makes them behave extremely. In this case, the pulsar is locked in a tight and extremely fast orbit, and over the last two decades, scientists have watched this orbit evolve rapidly compared with other objects in space that are larger, slower, and generally operating on a longer scale of time.

All of this means that for the first time, astrophysicists have recorded evidence of the predicted phenomenon of frame dragging. If spacetime is colloquially indeed a fabric, its an elastic one, where spinning objects receive that stored energy back from the fabric of spacetime itself. And objects within spacetime can pass energy back and forth the same way, making it both convenient and attractive, literally, to join into energy-saving pairs like this binary system.

The orbit of the two stars continues to drift and change, like a spinning figure skater who accelerates by pulling in their limbs. Its this change in speed and orientation that let scientists observe the frame dragging, in the form of an observable spin change called the Lense-Thirring effect. This detection is consistent with an evolutionary scenario in which the [white dwarf (WD)] accreted matter from the pulsar, spinning up the WD to a period of <200 seconds, this research team concludes.

Scientists have longed for evidence of frame dragging in the wild, so to speak, because the idea could explain a lot of things we dont understand yet about relativity, gravity itself, and forces that affect everything from celestial objects to subatomic particles. By observing a forceful and extremely fast binary star, these scientists have recorded what they say is the first such evidence, and the first step toward better understanding the universe.

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This Is Wild: Astrophysicists Can See Stars Twisting Space and Time - Popular Mechanics

The Crowd and the CosmosChris LintottOxford Univ., $24.95

Astrophysicist Chris Lintott had a problem back in themid-2000s. He wanted to know if the chemistry of star formation varies indifferent types of galaxies. But first he needed to sort through images ofhundreds of thousands of galaxies to gather an appropriate sample to study. Thetask would take many months if not longer for one person, and computers at thetime werent up to the challenge. So Lintott and colleagues turned to thepublic for help.

The group launched Galaxy Zoo in 2007. The website asked volunteers to classify galaxies by shape spiral or elliptical. Interest in the project was overwhelming. On the first day, so many people logged on that the server hosting the images crashed. Once the technical difficulties were resolved, more than 70,000 image classifications soon came in every hour. And as Lintott would learn, amateurs were just as good as professionals at categorizing galaxies.

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Galaxy Zoos success helped awaken other scientists to the potential of recruiting citizen scientists online to sift through large volumes of all sorts of data. That led to the birth of the Zooniverse, an online platform that lets anyone participate in real science. Projects on the platform ask volunteers to do everything from digitizing handwritten records from research ships to identifying animals caught on camera to sorting through telescope data to find signs of exoplanets.

In The Crowd and the Cosmos, Lintott, who cofounded the Zooniverse, shares his experiences with citizen science. The book is not a recounting of the history of Galaxy Zoo and the Zooniverse. Its more of an ode to citizen science. Lintott celebrates the successes, exploring the ways amateurs can contribute to science and how that contribution might change as artificial intelligence catches up with some kinds of human smarts.

By no means was Galaxy Zoo the first citizen scienceproject. As Lintott explains, the roots of citizen science go back to at leastthe 18th century. Even Charles Darwin benefited from observations contributedby a wide network of people. The Crowd and the Cosmos focuses on theimportance of citizen scientists in the age of big data and largely sticks towhat Lintott knows best: astrophysics and astronomy.

The book peruses a range of space topics, offering up-to-date,accessible overviews of exoplanets, supernovas, galaxies and dark energy, themysterious force that is causing the universes expansion to accelerate.Lintott is a knowledgeable and witty guide. His humor helps drive the story andeven pops up in numerous footnotes. After describing how he often ends talkswith the idea that, far into the future, the universe will likely become anearly empty void, a vast sea of space expanding forever into yet morenothingness, he quips: I do like to send an audience home happy.

Just as the universes future may seem bleak, so too mightthe future of some forms of citizen science. When Lintott first enlistedvolunteers to help wade through a deluge of galaxy images, computers wereterrible at tasks that required pattern-recognition skills. But times havechanged. Machine-learning algorithms abilities on visual tasks are improving,and researchers are on the verge of automating many time-intensive, oftentedious jobs. In fact, some Zooniverse projects today ask citizen scientists toclassify data as a way to amass large datasets to help train machine-leaningalgorithms. As artificial intelligence continues to get better, will there comea time when citizen scientists services are no longer needed?

Lintott doesnt think so. He predicts humans and machineswill keep working side by side, and at least for the foreseeable future,citizen scientists will still be needed to help train machine-learningalgorithms. But he also envisions these volunteers making other importantcontributions. For instance, he argues that when looking through seeminglyendless piles of images or historical records or even graphs of data, theseamateurs are in the best position to notice something rare or unusual; expertstend to be too focused on the task at hand, and computers might not be trainedto identify something out of the ordinary.

That was the case in 2007 when a volunteer in the Netherlands named Hanny van Arkel found a strange blob in an image and implored scientists to investigate. Dubbed Hannys Voorwerp (Dutch for object), the blob is now known to be a large gas cloud still glowing after being hit by a jet of radiation from a nearby galaxys black hole (SN: 12/23/17 & 1/6/18, p. 5). Researchers have learned that such gas clouds can be indicators that a now-quiet galaxy was active not too long ago (SN Online: 4/24/15).

Lintotts enthusiasm for citizen science and his admiration of the talents and tenacity of citizen scientists is inspiring. By the end of the book, I was ready to sign up for some projects in the Zooniverse.

Buy The Crowd and the Cosmos from Amazon.com.Science Newsis a participant in the Amazon Services LLC Associates Program. Please see ourFAQfor more details.

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An astrophysicist honors citizen scientists in the age of big data - Science News

How can we get a picture of the whole Milky Way if we are inside it? Good sleuthing is needed to combine all the clues, writes Chanda Prescod-Weinstein

By Chanda Prescod-Weinstein

ALL of the students in my astrophysics class last semester had to give a final presentation. In one, a student showed everyone an image of our galaxy, the Milky Way, as viewed from Earth. The student then showed another image of a spiral galaxy, suggesting that it reflected our own. Because it was a class focused on stars the students are taking on galaxies this semester a question came from the audience: how can we get a picture of the whole Milky Way if we are inside it? We cant.

In this sense, astrophysics is like a Midsomer

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Figuring out what the Milky Way looks like is akin to a murder mystery - New Scientist

Isha Salian, Corporate Communications, NVIDIA2020-02-01

The gallery of galaxy images astronomers produce is multiplying faster than the number of selfies on a teen's new smartphone.

Volunteers flocked to a recent crowdsource project, Galaxy Zoo, to help classify over a million galaxy images from the Sloan Digital Sky Survey. But citizen science can carry astrophysics only so far.

"Galaxy Zoo was a very successful endeavor, but the rate at which next-generation surveys will gather data will make crowdsourcing methods no longer scalable," said Asad Khan, a physics doctoral student at the University of Illinois at Urbana-Champaign. "This is where human-in-the-loop techniques present an approach to guide AI to data-driven discovery, including image classification."

Using transfer learning from the popular image classification model Xception, Khan and his fellow researchers developed a neural network that categorizes galaxy images as elliptical or spiral with expert-level accuracy. Classifying galaxy shapes helps scientists determine how old they are. It can also help them understand more complex questions about dark energy and how fast the universe is expanding.

Automating elements of galaxy classification enables astrophysicists to spend less time on basic labeling and focus on more complex research questions.

The research, the first application of deep transfer learning for galaxy classification, was one of six projects featured at the Scientific Visualization and Data Analytics Showcase at SC19, the annual supercomputing trade show.

AI Wrinkle in Time

The researchers trained the deep learning network on around 35,000 galaxy images from the Sloan Digital Sky Survey. Using Argonne National Laboratory's Cooley supercomputer, which is equipped with dozens of NVIDIA data center GPUs, the team accelerated neural network training from five hours to just eight minutes.

When tested on other images from the Sloan Digital Sky Survey, the AI achieved 99.8 percent accuracy for classifying images as either elliptical or spiral galaxies, an improvement compared to neural networks trained without transfer learning.

Using a single NVIDIA V100 Tensor Core GPU for inference, the team was able to classify 10,000 galaxies in under 30 seconds.

"We can already start using this network, or future versions of it, to start labeling the 300 million galaxies in the Dark Energy Survey," Khan said, "With GPU-accelerated inference, we could classify all the images in no time at all."

Khan and his team also developed a visualization to show how the neural network learned during training.

"Even if deep learning models can achieve impressive accuracy levels, when AI does make a mistake, we often don't know why," he said. "Visualizations like these can serve as a heuristic check on the network's performance, providing more interpretability for science communities."

The researchers next plan to study how the morphology of galaxies change with redshift, a phenomenon caused by the expansion of the universe.

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Spacing Out: How AI Provides Astronomers with Insights of Galactic Proportions - IT News Online

It seems almost ridiculous to say this, but of all the cultural influences I was exposed to as a kid the books, the movies, the music, current events the one thats stuck with me is Star Trek. I still think about the alternative reality I was presented by a second-rate TV show that lasted all of three seasons and 79 episodes.

Its easy to forget how bad the ratings were for the original show, which ran from 1966 to 1969, since its gone on to spawn more movies, sequels, books, games and toys than I can keep track of. But at the heart of it was a vision for the future that seems distressingly absent today.

Im not trying to cast a wondrous glow over the entire Star Trek endeavor. Some of the episodes were strikingly thought-provoking. Most were a combination of entertainment and morality plays. And some just plain stunk up the galaxy.

Yes, the original series projected a lot of the prejudices of its time, particularly when it came to women. The female crew members were basically eye candy, even if they possessed degrees in astrophysics, geology or whatever. Im pretty sure there isnt a person alive who would want to show up for work on a daily basis in a push-up bra, micro-mini and dominatrix boots. (Unless shes a professional dominatrix.)

Then there were the special effects. If you think they look tacky from your 2020 perspective, believe me, they looked just as bad when they were first aired in 1966. The show was produced on a shoestring budget and it seemed like most of the money for props went toward rolls of aluminum foil, Styrofoam rocks and remnants of shag carpeting.

But what many people tend to forget was how darned hopeful it all was. The ship and crew were only a microcosm of Earth. Here we caught a glimpse of a multi-ethnic, multi-colored crew whose goal was to seek out new life and new civilizations. This implied we believed we might actually have something to learn from the rest of the universe. (Today, were all convinced we already know everything and theres nothing to be learned from anyone outside of our political party, gender, race, class or nationality, much less from off-worlders.) The Enterprise explored to expand human knowledge, not to look for planets where we might conveniently dump all our garbage, our prison populations or our undesirables. (You can fill in the blank on that last one.)

We had eliminated poverty. We had cured disease. We had embraced a society where basic human needs were met. We had no pollution. We had a planet-wide government and we had peace. Nationalism did not exist unless you want to count Scotty and Chekhovs occasional sparring over the relative merits of Scotch versus vodka. No one was arguing about religion, although there was a lot of dialogue about faith and ethics.

Racism as we understand it today did not exist. Its true that one crew member endured a fair amount of verbal abuse, but he was getting picked on for having green blood and pointy ears. Maybe this wasnt such a positive harbinger of human nature, but at least Spock proved to be a disarmingly different target than the usual suspects.

Most of all, Star Trek promoted the idea that humanity had actually kept pace with technology. We had the means to wreak destruction on an unimaginable scale, but we had become more ethical and thoughtful (unless provoked).

Now the future is suddenly becoming a lot closer. The original show was set during the 2260s. That means we have a little more than 200 years to get ourselves out of the spiral of self-destruction we seem to be caught in. Our planet may not survive climate change. Our technological advancements suddenly seem a lot more threatening than promising. We have a bunch of super-duper deadly toys but we still have a Stone Age mentality.

We have an awful lot of catching up to do. Please, make it so.

Former Sentinel editor Susie Reing writes from Saxtons River, Vt. She can be reached at smrunlimited@gmail.com.

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I'd like to boldly go where everyone ought to be headed by now, by Susie Reing - The Keene Sentinel

Artists concept of Proxima Centauri b, an Earth-sized exoplanet orbiting the nearest star to our sun, Proxima Centauri. Now researchers think there is a second, larger planet also orbiting the star. Image via ESO/ M. Kornmesser/ Wikipedia.

In 2016, astronomers announced the discovery of an exoplanet orbiting the closest star to our solar system, Proxima Centauri. Exciting, since the planet appeared to be close to the same size as Earth and not too far away, cosmically-speaking, at 4.2 light-years. Could there be other planets in this nearby system? On January 15, 2020, another research team published its evidence for a second, larger planet orbiting Proxima Centauri. At this point, this second object is still considered a candidate. It is not confirmed. But researchers do make a compelling case for its existence.

The potential discovery was announced by Mario Damasso of theNational Institute of Astrophysics and his colleagues on January 15. The new peer-reviewed paper appeared in Science Advances on the same day.

The planet dubbed Proxima Centauri c is a fair bit larger than the first planet, Proxima Centauri b, and is about six times more massive than Earth. This would make it a super-Earth, planets that are significantly larger and more massive than Earth but smaller and less massive than Neptune. It is estimated to orbit its star every 5.2 years. Proxima Centauri b, by comparison, is only about 1.3 times Earths mass.

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Proxima Centauri as seen by the Hubble Space Telescope in 2013. Image via ESA/ Hubble/ Wikipedia.

Even though Proxima Centauri is the closest star, part of the Alpha Centauri three-star system, it has been difficult to detect planets orbiting it. Thats because most exoplanets discovered so far have been glimpsed via the transit method; that is, theyre detected because they lie edge-on to our line-of-sight to their host stars, and astronomers can detect a minute dip in the host stars light when the planet crosses in front of it. No such dip in brightness has been seen for Proxima Centauri.

Instead, to find this stars planets, astronomers have had to use a second planet-hunting technique, called the radial velocity method. Radial velocity refers to a slight wobble in the stars motion as seen from Earth, caused by the gravity of unseen planets tugging on it. This is how Proxima Centauri b was found, and now, seemingly, Proxima Centauri c.

Two European Southern Observatory (ESO) telescope instruments, the High Accuracy Radial velocity Planet Searcher (HARPS) and the Ultraviolet and Visual Echelle Spectrograph (UVES), were used to obtain the data from Proxima Centauri.

Damasso and his team analyzed the stars light spectrum data, going back 17.5 years, to see if a previously reported light spectrum signal really was from a second planet. If the spectrum oscillates between the red and blue radial velocity, that typically means the star is moving slightly closer to and then farther away from Earth, due to the gravitational pull of a planet or planets. The researchers did find such a signal, occurring over a 1,900-day period. That would mean it is unlikely to be due only to other cyclical shifts in the stars magnetic field. It would be more consistent with a second planet orbiting the star.

Our suns closest neighbors among the stars, including Proxima Centauri. Image via NASA PhotoJournal.

So, could either of these planets be habitable?

At this point, we just dont know enough about them to answer that question. Proxima Centauri b is almost the same size as Earth, and is thought to have similar temperatures, but it orbits very close to its star, which is a red dwarf. Red dwarfs are known for being very active, emitting powerful solar flares. The radiation from those flares could strip away the atmosphere of any close-in planets. Proxima Centauri c is farther out, but may be too cold for life as we know it. It also may be more like Neptune, with a deep gaseous atmosphere and no real solid surface, rather than a super-Earth, which is rocky like Earth, but larger. We just dont know yet.

Another exciting aspect of Proxima Centauri c, however, is that it is far enough from the glare of its star that it should be able to be photographed directly by upcoming space telescopes. So far, only a handful of planets that are much larger than this have been successfully photographed, and even then, they are still just blobs of light.

Mario Damasso of the National Institute of Astrophysics, whose team found the possible new planet. Image via Breakthrough/ YouTube.

From the paper:

Proxima c could become a prime target for follow-up and characterization with next-generation direct imaging instrumentation due to the large maximum angular separation of ~1 arc second from the parent star. The candidate planet represents a challenge for the models of super-Earth formation and evolution.

If scientists can learn more about both Proxima Centauri c and b, including direct imaging for at least c (b would be a lot more difficult), then that should give them a better idea of what both Earth-sized and super-Earth exoplanets are actually like, in particular ones that orbit red dwarf stars. That would then help them figure how many could be potentially habitable, and what conditions would make that possible, an exciting endeavor.

Bottom line: Researchers from theNational Institute of Astrophysics have found new evidence for a second planet orbiting Proxima Centauri, the closest star to our sun.

Source: A low-mass planet candidate orbiting Proxima Centauri at a distance of 1.5 AU

Via EurekAlert!

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Is there a 2nd planet orbiting Proxima Centauri? - EarthSky

One of the predictions of Einstein's general theory of relativity is that any spinning body drags the very fabric of space-time in its vicinity around with it. This is known as "frame-dragging".

In everyday life, frame-dragging is both undetectable and inconsequential, as the effect is so ridiculously tiny. Detecting the frame-dragging caused by the entire Earth's spin requires satellites such as the US$750 million Gravity Probe B, and the detection of angular changes in gyroscopes equivalent to just one degree every 100,000 years or so.

Luckily for us, the Universe contains many naturally occurring gravitational laboratories where physicists can observe Einstein's predictions at work in exquisite detail.

Our team's research, published today in Science, reveals evidence of frame-dragging on a much more noticeable scale, using a radio telescope and a unique pair of compact stars whizzing around each other at dizzying speeds.

The motion of these stars would have perplexed astronomers in Newton's time, as they clearly move in a warped space-time, and require Einstein's general theory of relativity to explain their trajectories.

An illustration of frame dragging. (Mark Myers/OzGrav ARC Centre of Excellence)

General relativity is the foundation of modern gravitational theory. It explains the precise motion of the stars, planets and satellites, and even the flow of time. One of its lesser-known predictions is that spinning bodies drag space-time around with them. The faster an object spins and the more massive it is, the more powerful the drag.

One type of object for which this is very relevant is called a white dwarf. These are the leftover cores from dead stars that were once several times the mass of our Sun, but have since exhausted their hydrogen fuel.

What remains is similar in size to Earth but hundreds of thousands of times more massive. White dwarfs can also spin very quickly, rotating every minute or two, rather than every 24 hours like Earth does.

The frame-dragging caused by such a white dwarf would be roughly 100 million times as powerful as Earth's.

That is all well and good, but we can't fly to a white dwarf and launch satellites around it. Fortunately, however, nature is kind to astronomers and has its own way of letting us observe them, via orbiting stars called pulsars.

Twenty years ago, CSIRO's Parkes radio telescope discovered a unique stellar pair consisting of a white dwarf (about the size of Earth but about 300,000 times heavier) and a radio pulsar (just the size of a city but 400,000 times heavier).

Compared with white dwarfs, pulsars are in another league altogether. They are made not of conventional atoms, but of neutrons packed tightly together, making them incredibly dense. What's more, the pulsar in our study spins 150 times every minute.

This mean that, 150 times every minute, a "lighthouse beam" of radio waves emitted by this pulsar sweeps past our vantage point here on Earth. We can use this to map the path of the pulsar as it orbits the white dwarf, by timing when its pulse arrives at our telescope and knowing the speed of light. This method revealed that the two stars orbit one another in less than 5 hours.

This pair, officially called PSR J1141-6545, is an ideal gravitational laboratory. Since 2001 we have trekked to Parkes several times a year to map this system's orbit, which exhibits a multitude of Einsteinian gravitational effects.

Mapping the evolution of orbits is not for the impatient, but our measurements are ridiculously precise. Although PSR J1141-6545 is several hundred quadrillion kilometres away (a quadrillion is a million billion), we know the pulsar rotates 2.5387230404 times per second, and that its orbit is tumbling in space.

This means the plane of its orbit is not fixed, but instead is slowly rotating.

When pairs of stars are born, the most massive one dies first, often creating a white dwarf. Before the second star dies it transfers matter to its white dwarf companion.

A disk forms as this material falls towards the white dwarf, and over the course of tens of thousands of years it revs up the white dwarf, until it rotates every few minutes.

A white dwarf being spun-up by the transfer of matter from its companion. (ARC Centre of Excellence for Gravitational Wave Discovery)

In rare cases such as this one, the second star can then detonate in a supernova, leaving behind a pulsar. The rapidly spinning white dwarf drags space-time around with it, making the pulsar's orbital plane tilt as it is dragged along. This tilting is what we observed through our patient mapping of the pulsar's orbit.

Einstein himself thought many of his predictions about space and time would never be observable. But the past few years have seen a revolution in extreme astrophysics, including the discovery of gravitational waves and the imaging of a black hole shadow with a worldwide network of telescopes. These discoveries were made by billion-dollar facilities.

Fortunately there is still a role in exploring general relativity for 50-year-old radio telescopes like the one at Parkes, and for patient campaigns by generations of graduate students.

Matthew Bailes, ARC Laureate Fellow, Swinburne University of Technology., Swinburne University of Technology and Vivek Venkatraman Krishnan, Scientific staff, Max Planck Institute.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Astronomers Have Caught a Star Literally Dragging Space-Time Around With It - ScienceAlert

Just over a century ago, Einstein predicted that the gravity of massive objects could warp spacetime.

In the past five years we've seen Einstein's theory of general relativity play out in the detection of gravitational waves, the imaging of a black hole, and the orbit of stars around the supermassive black hole at the centre of our galaxy.

And now, astronomers tracking a quirky pair of stars for 20 years using the Parkes radio telescope have proven him right again.

"This time we're seeing a spinning star at the centre of the system dragging the very fabric of spacetime with it," said astronomer and co-author Matthew Bailes of the Swinburne Institute of Technology.

In 1918, two Austrian scientists proposed that if Einstein was right then spinning objects, including Earth, should twist and drag the fabric of spacetime.

The phenomenon, known as the Lense-Thirring effect or frame-dragging, is usually too small to detect.

A tiny effect was first demonstrated in an experiment that measured the subtle movements of gyroscopes placed into space above Earth.

"We've discovered a system where the effect is 100 million times stronger than it is above the Earth," Professor Bailes said.

The discovery, by the international team of astronomers, is reported today in the journal Science.

The unusual star system known as PSR J1141-6545 was discovered around 10,000 light years away in the constellation of Musca aka The Fly in 2001.

At the heart is a fast-spinning white dwarf star the remains of an old star about the size of Earth but 300,000 times its density.

Every five hours it is circled by a neutron star (pulsar) the core of an exploded star no bigger than a city but about 100 billion times more dense than Earth.

The neutron star sends out regular pulses of high-energy particles like a lighthouse, which the astronomers used to track its orbit.

Over the years, the astronomers noticed the two stars got closer and closer as the white dwarf pulled its neighbour in.

"The orbit shrinks by about 7 millimetres a day," Professor Bailes said.

But as time went on, it became clear that the stars weren't acting as predicted by Einstein's theory.

"I had assumed that we'd done something wrong," Professor Bailes said.

It took four years of detective work by PhD student Vivek Venkatraman Krishnan and team members from the Max Planck Institute for Radio Astronomy to get to the bottom of the puzzle.

"After concluding that this could not have been due to problems with our telescopes, there was a brief period of time that I thought I disproved Einstein's theory," Dr Krishnan said.

In the end they twigged that the orbit of the pulsar was tumbling in space as it was being dragged around by the fast-spinning white dwarf star.

"While we knew that any body that rotates should drag space and time with it according to Einstein, we did not think that this would be measurable for this system," he said.

"This effect is usually expected to be measured only for a select class of heavenly bodies like some neutron stars and black holes."

But this was no ordinary pair of stars.

"The unique formation of this system made the white dwarf spin so fast that we could see its effects in the orbit, for the first time in any binary star system," Dr Krishnan said.

When the pulsar was born, material from the supernova fell onto the white dwarf, making it spin faster and faster.

The cataclysmic explosion also misaligned the spins of the two stars and changed the orbits of the pulsar from a normal circular path to an egg-shaped orbit, Professor Bailes said.

This enabled the astronomers to work out the white dwarf was spinning about once every minute.

"That is causing the fabric of spacetime to be ripped around much more strongly than it would be above the Earth," Professor Bailes said.

This is a very unusual system, said Susan Scott, an astrophysicist at the Australian National University who was not involved in the discovery.

"There's only two confirmed binary systems like that where the white dwarf is known to have formed before the other companion," she said.

But the two stars in this system are much closer together.

Professor Scott said the discovery is "an exciting new example" of testing Einstein's theories in "a different realm of gravity" in the same way the detection of gravitational waves did.

"There are very few things in life where you have to put general relativity in to make them completely accurate. That's because we live in a place of very low gravity.

"But out there in the universe there are places with very high gravity and you need to consider these general relativity effects because they make a difference."

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Space-warping star system proves Einstein's general theory of relativity right. Again - ABC News

STOCKHOLM, Jan. 30, 2020 /PRNewswire/ -- The man who discovered the solar wind, Eugene Parker, and one of mathematics' great problem-solvers, Enrico Bombieri, will receive this year's Crafoord Prize in astronomy and mathematics, respectively. The Crafoord Prize is worth six million Swedish kronaand is awarded by the Royal Swedish Academy of Sciences in partnership with the Crafoord Foundation in Lund.

The Parker Solar Probe is currently on its way to the sun.It was launched by NASA in 2018 and its first results were reported just before Christmas. This probe is the first to be named after a living person - Eugene N. Parker, professor emeritus at the University of Chicago, USA.

Eugene Parker is responsible for several fundamental discoveries about the gases that surround the sun and other stars.He has also developed the theory of how the solar wind arises and how magnetic fields arise and change in space. When he initially presented his theories, over fifty years ago, they were strongly challenged, but were later confirmed through observations from spacecrafts.

Eugene Parker was the first person to realise that the sun is not in equilibrium, as was previously thought.Quite the opposite, it releases mass; the charged gas of ions and electrons that makes up the sun's "atmosphere" is expanding as a solar wind that stretches throughout our planetary system. His ideas are also the foundation for all the forecasts about the space weather, which can disrupt satellites and cause power outages here on Earth.

He will now receive the Crafoord Prize in Astronomy "for pioneering and fundamental studies of the solar wind and magnetic fields from stellar to galactic scales".

Eugene Parker was stunned into silence when he was told about the award:

"It took my breath away. I didn't do anything for a few minutes. I of course knew about the Crafoord Prize, so I was surprised, pleasantly so."

Passionate about number theory

At the same time Enrico Bombieri from the Institute for Advanced Study, Princeton, USA, will receive the Crafoord Prize in Mathematics "for outstanding and influential contributions in all the major areas of mathematics, particularly number theory, analysis and algebraic geometry".

Enrico Bombieri belongs to an increasingly rare group of mathematicians who can solve problems in almost all areas of mathematics.However, his greatest passion has always been number theory, which is the study of integers.He was just 16 years old when he published his first work in number theory and among other things, he is a leading expert on the Riemann hypothesis on the distribution of prime numbers.

Enrico Bombieri has made significant contributions in algebra, advanced geometry and complex analysis.He has also contributed to solving Bernstein's problem.This is a variation of Plateau's problem, about how to mathematically describe the shape of the soap film that forms when a wire frame is dipped into a soap solution.

Enrico Bombieri has visited Sweden and the Royal Swedish Academy of Sciences' Institut Mittag-Leffler on numerous occasions. He was delighted to discover that he has been awarded the Crafoord Prize in Mathematics.

"It came as a complete surprise.I have received a few prizes before, but I'm especially pleased with this one because of my connection with Swedish mathematicians", he commented on learning of the prize.

FACTS about the prize

The Crafoord Prize is awarded in partnership between the Royal Swedish Academy of Sciences and the Crafoord Foundation in Lund. The Academy is responsible for selecting the Laureates. The disciplines, which change every year, are mathematics and astronomy, geosciences, biosciences and polyarthritis (e.g. rheumatoid arthritis). The prize in polyarthritis is awarded only when scientific progress in this field has been such that an award is justified. The prize disciplines are chosen as a complement to the Nobel Prizes.

This year's Laureates in mathematics and astronomy each receive six million Swedish krona. The prize ceremony will be held in Stockholm on May 15 in the presence of H.M. King CarlXVI Gustaf and H.M. Queen Silvia.

FACTS about the Laureates

Astronomy

Eugene N. Parker, S. Chandrasekhar Distinguished Service Professor Emeritus, Department of Astronomy and Astrophysics, Enrico Fermi Institute, University of Chicago, USA.He was born in 1927 in Houghton, USA, and received his Ph.D. in 1951 from the California Institute of Technology, Caltech, Pasadena, USA.

Story continues

Mathematics

Enrico Bombieri, Professor Emeritus, School of Mathematics, Institute for Advanced Study, Princeton, USA.He was born in 1940 in Milan, Italy and received his Ph.D. in 1963 from the Universit degli Studi di Milano.

Contacts:ExpertsAstronomyJan-Erik WahlundMember of the Royal Swedish Academy of SciencesAssociate Professor at the Swedish Institute of Space Physics and the Department of Physics and Astronomy at Uppsala Universityjwe@irfu.se +46-(0)76-769-7877

MathematicsAri LaptevMember of the Royal Swedish Academy of SciencesProfessor Emeritus of Mathematics at KTH Royal Institute of Technology, Stockholm, and Professor at Imperial College Londonlaptev@kth.se +46-(0)76-677-88-10

Press contact:Eva Nevelius,Press Secretary at the Royal Swedish Academy of Scienceseva.nevelius@kva.se +46-(0)70-878-6763

Videos about the price in mathematics and astronomy and pictures of the laureates that can be downloaded can be found at http://www.kva.se

This information was brought to you by Cision http://news.cision.com

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SOURCE The Royal Swedish Academy of Sciences/The Crafoord Prize

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Crafoord Laureates Discovered the Solar Wind and Solved Mathematical Problems - Yahoo Finance

At the center of our galaxy lies a region where roughly 10 million stars are packed into just 1 parsec (3.25 light-years) of space. At the center of this lies the supermassive black hole (SMBH) known as Sagittarius A*, which has a mass of over 4 million Suns. For decades, astronomers have been trying to get a better look at this region in the hopes of understanding the incredible forces at work and how they have affected the evolution of our galaxy.

What theyve found includes a series of stars that orbit very closely to Sagittarius A* (like S1 and S2), which have been used to test Einsteins Theory of General Relativity. And recently, a team from UCLAs Galactic Center Orbits Initiative detected a series of compact objects that also orbit the SMBH. These objects look like clouds of gas but behave like stars, depending on how close they are in their orbits to Sagittarius A*.

The study that describes their findings, which recently appeared in the journal Nature, was led by Dr. Anna Ciurlo of the University of California, Los Angeles (UCLA). As they indicate in their study, these objects orbit our galaxys SMBH with a period of between 100 to 1,000 years. These objects look compact most of the time but stretch out when they are at the closest point in their orbits to the black hole.

Their work builds on about fifteen years of observations that have identified more and more of these objects near the center of our galaxy. The first object (later named G1) was discovered in 2005 by a team led by Andrea Ghez, the Lauren B. Leichtman and Arthur E. Levine Professor of Astrophysics the director of theUCLA Galactic Center Group and a co-author on this study.

This was followed in 2012 when Prof. Ghez and her colleagues found a second object (G2) that made a close approach to Sagittarius A* in 2014. Initially, G1 and G2 were thought to be gas clouds until they made their closest approach to the Sagittarius A*s and were not shredded by the SMBHs gravitational pull (which is what happens normally to gas clouds when approaching a black hole). As Ghez explained:

At the time of closest approach, G2 had a really strange signature. We had seen it before, but it didnt look too peculiar until it got close to the black hole and became elongated, and much of its gas was torn apart. It went from being a pretty innocuous object when it was far from the black hole to one that was really stretched out and distorted at its closest approach and lost its outer shell, and now its getting more compact again.

In 2018, Dr. Cuirlo and an international team of astronomers (which included Prof. Ghez) used twelve years of data gathered by the W.M. Keck Observatory and adaptive optics technology (which Prof. Ghez helped pioneer) to identify three more of these objects (G3, G4, and G5) near the galaxys center. Since that time, a total of six objects have been identified in this region (G1 G6).

In this most recent study, the team led by Dr. Cuirlo used 13 years of near-infrared data obtained by the W.M. Kecks OSIRIS integral field spectrometer to examine the orbits of these six objects. Astronomers are exciting to study these objects because they provide astronomers with an opportunity to test General Relativity something which Prof. Ghez and her colleagues did in the summer of 2019.

And as Mark Morris a UCLA professor of physics and astronomy and a co-author on the study explained, the fate of these objects is something astronomers want to know because it expected to be quite spectacular.

One of the things that has gotten everyone excited about the G objects is that the stuff that gets pulled off of them by tidal forces as they sweep by the central black hole must inevitably fall into the black hole, he said. When that happens, it might be able to produce an impressive fireworks show since the material eaten by the black hole will heat up and emit copious radiation before it disappears across the event horizon.

In the course of observing the Milky Ways central region, the research group has reported the existence of six objects so far. However, they also noticed that while G1 and G2 have very similar orbits, the other four objects differ considerably. This naturally gives rise to the question of whether all six are a similar class of objects, or G1 and G2 are outliers.

Addressing this, Ghez and her colleagues believe that all six objects were binary stars that merged because of the SMBHs strong gravitational force. This process would have taken more than 1 million years to complete and could be an indication that binary star mergers are actually quite common. As Ghez explained:

Black holes may be driving binary stars to merge. Its possible that many of the stars weve been watching and not understanding may be the end product of mergers that are calm now. We are learning how galaxies and black holes evolve. The way binary stars interact with each other and with the black hole is very different from how single stars interact with other single stars and with the black hole.

Another interesting observation, which Ghezs team reported on back in September of 2019, is the fact that Sagittarius A* has been growing brighter in the past 24 years an indication that it is consuming more matter. Similarly, the stretching of G2 that was observed in 2014 appeared to pull gas away from it that may have been recently consumed by the black hole.

This could be an indication that the stellar mergers taking place in its vicinity are feeding Sagittarius A*. The most recent observations also showed that while the gas from G2s outer shell was stretched dramatically, the dust contained inside did not get stretched much. This means that something kept the dust compact, which is compelling evidence that star could be inside G2.

As Ciurlo said, this discovery was made possible thanks to decades worth of observations by the UCLA Galactic Center Group.

The unique dataset that Professor Ghezs group has gathered during more than 20 years is what allowed us to make this discovery. We now have a population of G objects, so it is not a matter of explaining a one-time event like G2.

Meanwhile, the team has already identified a few other candidates that could belong to this new class of objects and are continuing to analyze them. Ultimately, this research will help astronomers to understand what is happening in the majority of galaxies and how interactions between stars and SMBHs in their cores are helping to drive their evolution.

The Earth is in the suburbs compared to the center of the galaxy, which is some 26,000 light-years away, said Ghez. The center of our galaxy has a density of stars 1 billion times higher than our part of the galaxy. The gravitational pull is so much stronger. The magnetic fields are more extreme. The center of the galaxy is where extreme astrophysics occurs the X-sports of astrophysics.

Further Reading: UCLA, Nature

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More Mysterious Space Blobs Have Been Found Near the Center of the Milky Way - Universe Today

Each of these Hubble Space Telescope snapshots reveals four distorted images of a background quasar surrounding the central core of a foreground massive galaxy.The multiple quasar images were produced by the gravity of the foreground galaxy, which is acting like a magnifying glass by warping the quasars light in an effect called gravitational lensing. Quasars are extremely distant cosmic streetlights produced by active black holes.The light rays from each lensed quasar image take a slightly different path through space to reach Earth. The pathways length depends on the amount of matter that is distorting space along the line of sight to the quasar. To trace each pathway, the astronomers monitor the flickering of the quasars light as its black hole gobbles up material. When the light flickers, each lensed image brightens at a different time. This flickering sequence allows researchers to measure the time delays between each image as the lensed light travels along its path to Earth.These time-delay measurements helped astronomers calculate how fast the universe is growing, a value called the Hubble constant.The Hubble images were taken between 2003 and 2004 with the Advanced Camera for Surveys.Credit: NASA, ESA, S.H. Suyu (Max Planck Institute for Astrophysics, Technical University of Munich, and Academia Sinica Institute of Astronomy and Astrophysics), and K.C. Wong (University of Tokyos Kavli Institute for the Physics and Mathematics of the Universe)

People use the phrase Holy Cow to express excitement. Playing with that phrase, researchers from an international collaboration developed an acronymH0LiCOWfor their projects name that expresses the excitement over their Hubble Space Telescope measurements of the universes expansion rate.

Knowing the precise value for how fast the universe expands is important for determining the age, size, and fate of the cosmos. Unraveling this mystery has been one of the greatest challenges in astrophysics in recent years.

Members of the H0LiCOW (H0 Lenses in COSMOGRAILs Wellspring) team used Hubble and a technique that is completely independent of any previous method to measure the universes expansion, a value called the Hubble constant.

This latest value represents the most precise measurement yet using the gravitational lensing method, where the gravity of a foreground galaxy acts like a giant magnifying lens, amplifying and distorting light from background objects. This latest study did not rely on the traditional cosmic distance ladder technique to measure accurate distances to galaxies by using various types of stars as milepost markers. Instead, the researchers employed the exotic physics of gravitational lensing to calculate the universes expansion rate.

The researchers result further strengthens a troubling discrepancy between the expansion rate calculated from measurements of the local universe and the rate as predicted from background radiation in the early universe, a time before galaxies and stars even existed. The new study adds evidence to the idea that new theories may be needed to explain what scientists are finding.

This graphic lists the variety of techniques astronomers have used to measure the expansion rate of the universe, known as the Hubble constant. Knowing the precise value for how fast the universe expands is important for determining the age, size, and fate of the cosmos.One set of observations looked at the very early universe. Based on those measurements, astronomers calculated a Hubble constant value. A second set of observation strategies analyzed the universes expansion in the local universe.The challenge to cosmologists is that these two approaches dont arrive at the same value. Its just as perplexing as two opposite sections of a bridge under construction not lining up. Clearly something is wrong, but what? Astrophysicists may need to rethink their ideas about the physical underpinnings of the observable universe.The top half of the illustration outlines the seven different methods used to measure the expansion in the local universe. The letters corresponding to each technique are plotted on the bridge on the right. The location of each dot on the bridge road represents the measured value of the Hubble constant, while the length of the associated bar shows the estimated amount of uncertainty in the measurements. The seven methods combined yield an average Hubble constant value of 73 kilometers per second per megaparsec.This number is at odds with the combined value of the techniques astronomers used to calculate the universes expansion rate from the early cosmos (shown in the bottom half of the graphic). However, these five techniques are generally more precise because they have lower estimated uncertainties, as shown in the plot on the bridge road. Their combined value for the Hubble constant is 67.4 kilometers per second per megaparsec.Credit: NASA, ESA, and A. James (STScI)

A team of astronomers using NASAs Hubble Space Telescope has measured the universes expansion rate using a technique that is completely independent of any previous method.

Knowing the precise value for how fast the universe expands is important for determining the age, size, and fate of the cosmos. Unraveling this mystery has been one of the greatest challenges in astrophysics in recent years. The new study adds evidence to the idea that new theories may be needed to explain what scientists are finding.

The researchers result further strengthens a troubling discrepancy between the expansion rate, called the Hubble constant, calculated from measurements of the local universe and the rate as predicted from background radiation in the early universe, a time before galaxies and stars even existed.

This latest value represents the most precise measurement yet using the gravitational lensing method, where the gravity of a foreground galaxy acts like a giant magnifying lens, amplifying and distorting light from background objects. This latest study did not rely on the traditional cosmic distance ladder technique to measure accurate distances to galaxies by using various types of stars as milepost markers. Instead, the researchers employed the exotic physics of gravitational lensing to calculate the universes expansion rate.

Annotated Compass Image of Gravitationally Lensed Quasars. Credit: NASA, ESA, S.H. Suyu (Max Planck Institute for Astrophysics, Technical University of Munich, and Academia Sinica Institute of Astronomy and Astrophysics), and K.C. Wong (University of Tokyos Kavli Institute for the Physics and Mathematics of the Universe)

The astronomy team that made the new Hubble constant measurements is dubbed H0LiCOW (H0 Lenses in COSMOGRAILs Wellspring). COSMOGRAIL is the acronym for Cosmological Monitoring of Gravitational Lenses, a large international project whose goal is monitoring gravitational lenses. Wellspring refers to the abundant supply of quasar lensing systems.

The research team derived the H0LiCOW value for the Hubble constant through observing and analysis techniques that have been greatly refined over the past two decades.

H0LiCOW and other recent measurements suggest a faster expansion rate in the local universe than was expected based on observations by the European Space Agencys Planck satellite of how the cosmos behaved more than 13 billion years ago.

The gulf between the two values has important implications for understanding the universes underlying physical parameters and may require new physics to account for the mismatch.

If these results do not agree, it may be a hint that we do not yet fully understand how matter and energy evolved over time, particularly at early times, said H0LiCOW team leader Sherry Suyu of the Max Planck Institute for Astrophysics in Germany, the Technical University of Munich, and the Academia Sinica Institute of Astronomy and Astrophysics in Taipei, Taiwan.

The H0LiCOW team used Hubble to observe the light from six faraway quasars, the brilliant searchlights from gas orbiting supermassive black holes at the centers of galaxies. Quasars are ideal background objects for many reasons; for example, they are bright, extremely distant, and scattered all over the sky. The telescope observed how the light from each quasar was multiplied into four images by the gravity of a massive foreground galaxy. The galaxies studied are 3 billion to 6.5 billion light-years away. The quasars average distance is 5.5 billion light-years from Earth.

The light rays from each lensed quasar image take a slightly different path through space to reach Earth. The pathways length depends on the amount of matter that is distorting space along the line of sight to the quasar. To trace each pathway, the astronomers monitor the flickering of the quasars light as its black hole gobbles up material. When the light flickers, each lensed image brightens at a different time.

This flickering sequence allows researchers to measure the time delays between each image as the lensed light travels along its path to Earth. To fully understand these delays, the team first used Hubble to make accurate maps of the distribution of matter in each lensing galaxy. Astronomers could then reliably deduce the distances from the galaxy to the quasar, and from Earth to the galaxy and to the background quasar. By comparing these distance values, the researchers measured the universes expansion rate.

The length of each time delay indicates how fast the universe is expanding, said team member Kenneth Wong of the University of Tokyos Kavli Institute for the Physics and Mathematics of the Universe, lead author of the H0LiCOW collaborations most recent paper. If the time delays are shorter, then the universe is expanding at a faster rate. If they are longer, then the expansion rate is slower.

The time-delay process is analogous to four trains leaving the same station at exactly the same time and traveling at the same speed to reach the same destination. However, each of the trains arrives at the destination at a different time. Thats because each train takes a different route, and the distance for each route is not the same. Some trains travel over hills. Others go through valleys, and still others chug around mountains. From the varied arrival times, one can infer that each train traveled a different distance to reach the same stop. Similarly, the quasar flickering pattern does not appear at the same time because some of the light is delayed by traveling around bends created by the gravity of dense matter in the intervening galaxy.

The researchers calculated a Hubble constant value of 73 kilometers per second per megaparsec (with 2.4% uncertainty). This means that for every additional 3.3 million light-years away a galaxy is from Earth, it appears to be moving 73 kilometers per second faster, because of the universes expansion.

The teams measurement also is close to the Hubble constant value of 74 calculated by the Supernova H0 for the Equation of State (SH0ES) team, which used the cosmic distance ladder technique. The SH0ES measurement is based on gauging the distances to galaxies near and far from Earth by using Cepheid variable stars and supernovas as measuring sticks to the galaxies.

The SH0ES and H0LiCOW values significantly differ from the Planck number of 67, strengthening the tension between Hubble constant measurements of the modern universe and the predicted value based on observations of the early universe.

One of the challenges we overcame was having dedicated monitoring programs through COSMOGRAIL to get the time delays for several of these quasar lensing systems, said Frdric Courbin of the Ecole Polytechnique Fdrale de Lausanne, leader of the COSMOGRAIL project.

Suyu added: At the same time, new mass modeling techniques were developed to measure a galaxys matter distribution, including models we designed to make use of the high-resolution Hubble imaging. The images enabled us to reconstruct, for example, the quasars host galaxies. These images, along with additional wider-field images taken from ground-based telescopes, also allow us to characterize the environment of the lens system, which affects the bending of light rays. The new mass modeling techniques, in combination with the time delays, help us to measure precise distances to the galaxies.

Begun in 2012, the H0LiCOW team now has Hubble images and time-delay information for 10 lensed quasars and intervening lensing galaxies. The team will continue to search for and follow up on new lensed quasars in collaboration with researchers from two new programs. One program, called STRIDES (STRong-lensing Insights into Dark Energy Survey), is searching for new lensed quasar systems. The second, called SHARP (Strong-lensing at High Angular Resolution Program), uses adaptive optics with the W.M. Keck telescopes to image the lensed systems. The teams goal is to observe 30 more lensed quasar systems to reduce their 2.4% percent uncertainty to 1%.

NASAs upcoming James Webb Space Telescope, expected to launch in 2021, may help them achieve their goal of 1% uncertainty much faster through Webbs ability to map the velocities of stars in a lensing galaxy, which will allow astronomers to develop more precise models of the galaxys distribution of dark matter.

The H0LiCOW teams work also paves the way for studying hundreds of lensed quasars that astronomers are discovering through surveys such as the Dark Energy Survey and PanSTARRS (Panoramic Survey Telescope and Rapid Response System), and the upcoming National Science Foundations Large Synoptic Survey Telescope, which is expected to uncover thousands of additional sources.

In addition, NASAs Wide Field Infrared Survey Telescope (WFIRST) will help astronomers address the disagreement in the Hubble constant value by tracing the expansion history of the universe. The mission will also use multiple techniques, such as sampling thousands of supernovae and other objects at various distances, to help determine whether the discrepancy is a result of measurement errors, observational technique, or whether astronomers need to adjust the theory from which they derive their predictions.

The team will present its results at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii.

The Hubble Space Telescope is a project of international cooperation between the European Space Agency (ESA) and NASA. 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.

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H0LiCOW! Cosmic Magnifying Glasses Yield Independent Measure of Universe's Expansion That Adds to Troubling Discrepancy - SciTechDaily

A 17-year-old from Scarsdale, New York discovered a new planet on his third day of a two-month internship at NASA Goddard Space Flight Center.

During the internship last year, Wolf Cukier was tasked with examining variations in the brightness of stars within data captured by NASA's Transiting Exoplanet Survey Satellite, or TESS for short.

"I worked with [NASA scientist] Veselin Kostov and with him I worked on finding a circumbinary planet in the TESS data," Cukier told Newsweek. "It was exciting because 1) I was actually able to do research that summer, which is cool, and 2) I was able to work in an area of science that I really enjoy. And 3) I was at NASA, which is just a cool place."

Circumbinary planets are worlds which orbit two starssomething which had never been discovered before in the TESS data. But just three days into the internship, Cukier was able to identify one of these worlds in a star system located around 1,300 light-years away.

"I was pretty excited. Coming into the internship, it would be hard to say that I expected to find a planet. 'Hope' is probably the best word to use there, because there are a total of 12 previously discovered transiting circumbinary planets that were known at the time," Cukier said. "That's 12 I think in 10 years. So they aren't impossible to find but they're not very common to find either. And also tests had yet to find any circumbinary planets. So finding this one was especially cool."

"The TESS data, at the time, was still under a year old," Cukier said. "So finding one just that early in general was fun. And also I don't think [my manager] expected me to find one so early either."

The planetdubbed TOI 1338 bis thought to be around seven times larger than the Earth and it orbits the two stars in almost exactly the same plane, meaning it experiences regular stellar eclipses. The two stars in the system orbit each other every 15 days, according to NASA.

A paper regarding the discoverywhich is co-authored by Cukier, alongside scientists from Goddard and several other institutionshas been submitted for publication in a scientific journal.

On the back of his successful internship at the space agency, Cukier said the next step for him is college.

"My top three choices are Princeton, Stanford and MIT. We shall see what happens in the application process. I intend to study physics or astrophysicsdepends which college I end up going to because some only offer physics and some offer astrophysics in addition."

"Then I will see what happens from there," he said. "Being a research scientist or a professor are appealing options, however, that's a bit in the future for me to predict how my life will turn out."

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NASA Intern Discovered New Planet With Two Suns on Third Day of Placement - Newsweek

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Molecules containing noble gases shouldn't exist. By definition, these chemical elements helium, neon, argon, krypton, xenon, and radon are the party poopers of the periodic table, huddling in the rightmost column and refusing to make molecules. Indeed, no one has ever seen any naturally occurring noble gas molecules on Earth. Earlier this decade, though, astronomers accidentally discovered one of these aloof elements in molecules in space.

Then, in 2019, observers reported finding a second kind of noble gas molecule, one they had sought for more than three decades and of a type that was the very first to form after the universe's birth in the big bang. This newly found molecule lends insight into the chemistry of the early universe, before any stars began to shine or any galaxies had formed. The discovery may even help astronomers understand how the first stars arose.

Most chemical elements readily share electrons with other elements to make molecules, but noble gases normally don't. "Noble gases are in some sense happy as they are," says Peter Schilke, an astrophysicist at the University of Cologne in Germany. That's because the outer shell of a noble gas atom already has its fill of electrons, so it won't ordinarily exchange electrons to bond with other atoms and form molecules at least, not here on Earth.

In retrospect, space seems the perfect place to seek noble gas molecules, because these gases abound in the cosmos. Helium is the second most common element in the universe, after hydrogen, and neon ranks fifth or sixth. And in interstellar space, where extreme temperatures and densities are the rule, noble gases do things they would never do on Earth. That includes forming molecules.

In addition to providing insight into the universe's infancy, these exotic molecules tell scientists about the current conditions in the space between the stars the gases that make up the interstellar medium which is of intense interest to astronomers. "The interstellar medium is the place where stars and planetary systems are born," says Maryvonne Gerin, an astrophysicist at the Observatory of Paris and coauthor of a 2016 Annual Review of Astronomy and Astrophysics article on interstellar molecules.

For decades astronomers have pursued one noble gas molecule in particular: helium hydride, or HeH+, made of the two most common elements in the universe and thus a good bet to exist in space. Though naturally occurring helium hydride has never been found on Earth, scientists were able to force the two atoms together in the lab almost a century ago.

So it seemed this combo would be the most likely quarry for astronomers as well. Instead, they were caught off guard by an even stranger molecule.

An interstellar embarrassment

Argon is more than 20 times as common in Earth's atmosphere as carbon dioxide but gets far less press. In fact, it is the third most abundant gas in the air you breathe. Nitrogen and oxygen make up 78 percent and 21 percent of Earth's atmosphere, respectively, while argon accounts for most of the remaining 1 percent.

But nobody was looking for an interstellar molecule containing argon. "It was basically a serendipitous discovery," says University College London astrophysicist Mike Barlow, who led the team that accidentally found ArH+: argonium, which consists of argon and hydrogen.

Another noble gas element helped to make the find possible. In 2009 the Herschel Space Observatory lifted off for space and literally kept its cool during the mission by carrying a tank of frigid liquid helium that lasted four years. This allowed Herschel to observe far-infrared wavelengths from distant objects without the interference its own warmth would have produced. Because many molecules absorb and emit far-infrared light, this spectral range is a good place to seek new space molecules.

Within a year of Herschel's launch, astronomers began noticing that something in interstellar space was absorbing far-infrared light at a wavelength of 485 microns, a spectral line that hadn't been observed before. "Nobody could figure out what it was," says David Neufeld, an astrophysicist at Johns Hopkins University and coauthor of the 2016 Annual Review article (and an acquaintance of the author of this story in graduate school).

Schilke consulted colleagues in his group at Cologne and elsewhere. "We sat in the office at the whiteboard," he says, "and we put all the possible molecules on there, including argonium." No known molecule matched the observed wavelength of 485 microns.

Meanwhile, Barlow's team was using Herschel data to study the Crab Nebula, the remains of a massive star our ancestors saw explode in the year 1054. The celestial fireworks forged argon and other "metals," which astronomers define as all elements heavier than helium.

Another view of the Crab Nebula, the remnants of a supernova explosion witnessed by skywatchers in Japan and China a thousand years ago. Orange filaments reveal the hydrogen that once constituted the star; the blue glow is produced by the neutron star at the nebulas center. Study of the light from the object revealed the presence of argonium. | (NASA / ESA / J. HESTER ARIZONA STATE UNIVERSITY)

In the nebula's argon-rich gas, Barlow and his colleagues spotted two unidentified spectral lines. One was the same mysterious line everyone else had been seeing at 485 microns; the other had exactly half the wavelength the hallmark of a molecule containing two atoms. Barlow identified it as argonium, publishing the discovery in 2013. It was the first noble gas molecule ever found in nature. (Barlow notes that at the last minute the editors of his scientific paper changed "molecule" in the title to "molecular ion.")

The discovery was a shock. "We were just stunned when we heard this," Neufeld says. After all, astronomers had been seeing that same 485-micron spectral line elsewhere. "When I first heard about the detection," Schilke says, "I was extremely embarrassed that we had not spotted this ourselves."

The scientists were the victims of a down-to-earth mix-up. They thought they knew the wavelengths argonium produced, because scientists had created it in the lab decades earlier and measured its spectrum. But these laboratory molecules contained argon-40, which is by far the most common argon isotope on Earth. But that's only because the argon we breathe comes from the radioactive decay of potassium-40 in rocks.

The universe is different. "In the interstellar medium," says Schilke, "argon-36 is by far the most abundant, and we were just too stupid to realize it." Argonium made with argon-36 absorbs and emits light at slightly different wavelengths than it does with argon-40, explaining why the scientists had missed the identification.

Nevertheless, once they recognized the existence of interstellar argonium, Schilke, Neufeld, Gerin, and their colleagues sought to explain its formation. "This is a molecule that doesn't like molecules," Schilke says, just as argon is an atom that doesn't like atoms. This peculiar characteristic is turning out to be useful.

Argonium's cosmic origins

Based on standard calculations of how chemical reactions proceed in space, scientists know the formation of the interstellar argonium molecule requires two steps. First, a cosmic ray a high-speed charged particle strips an electron from an interstellar argon atom, making Ar+. Then that argon ion can steal a hydrogen atom from a hydrogen molecule (H2) to create argonium, ArH+, because the hydrogen atom is more attracted to the argon ion than to its hydrogen mate.

But argonium is fragile, and the same hydrogen molecules it requires for its formation can also destroy it. The noble gas molecule can therefore exist only where there's just enough molecular hydrogen to create argonium but not so much as to tear it apart. This stringent requirement turns out to be handy for identifying which interstellar clouds aren't likely to spawn new stars and planets.

Interstellar gas in our part of the Milky Way comes in two main types: atomic and molecular. The first and more common type consists primarily of individual hydrogen and helium atoms. Because atomic gas is diffuse, it rarely makes new stars. Instead, most stars arise in denser gas where atoms crowd together to create molecules.

It can be difficult to tell apart the interstellar clouds that consist mostly of atomic gas from those that consist mostly of molecular gas, and that's where argonium comes in. "It's a tracer of almost purely atomic gas," Schilke says. In fact, although argonium is a molecule, it exists only in gas that's 99.9 to 99.99 percent atomic.

Because cosmic rays lead to the creation of argonium, its abundance in interstellar space has also helped nail down the number of cosmic rays darting through the galaxy. "There are more cosmic rays than we thought before," Gerin says. That's important not only for future Captain Kirks wishing to minimize their exposure to the destructive radiation as they travel between star systems, but also to scientists studying the chemistry of the interstellar medium, because cosmic rays are the first step in the creation of other molecules as well.

Read the rest of the story at Knowable Magazine.

This article originally appeared in Knowable Magazine, an independent journalistic endeavor from Annual Reviews. Sign up for the newsletter.

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Space is the place for impossible molecules - The Week Magazine

Warm, cold, just right? Physicists at the University of California, Davis, are taking the temperature of dark matter, the mysterious substance that makes up about a quarter of our universe.

We have very little idea of what dark matter is, and physicists have yet to detect a dark matter particle. But we do know that the gravity of clumps of dark matter can distort light from distant objects. Chris Fassnacht, a physics professor at UC Davis, and colleagues are using this distortion, called gravitational lensing, to learn more about the properties of dark matter.

The standard model for dark matter is that it is cold,meaning that the particles move slowly compared to the speed of light, Fassnacht said. This is also tied to the mass of dark matter particles. The lower the mass of the particle, the warmer it is and the faster it will move.

The model of cold (more massive) dark matter holds at very large scales, Fassnacht said, but doesnt work so well on the scale of individual galaxies. Thats led to other models including warmdark matter with lighter, faster-moving particles. Hot dark matter with particles moving close to the speed of light has been ruled out by observations.

Former UC Davis graduate student Jen-Wei Hsueh, Fassnacht and colleagues used gravitational lensing to put a limit on the warmth and therefore the mass of dark matter. They measured the brightness of seven distant gravitationally lensed quasars to look for changes caused by additional intervening blobs of dark matter and used these results to measure the size of these dark matter lenses.

If dark matter particles are lighter, warmer and more rapidly moving, then they will not form structures below a certain size, Fassnacht said.

Below a certain size, they would just get smeared out, he said.

The results put a lower limit on the mass of a potential dark matter particle while not ruling out cold dark matter, he said. The teams results represent a major improvement over a previous analysis, from 2002, and are comparable to recent results from a team at UCLA.

Fassnacht hopes to continue adding lensed objects to the survey to improve the statistical accuracy.

We need to look at about 50 objects to get a good constraint on how warm dark matter can be, he said.

A paper describing the work is published in the Monthly Notices of the Royal Astronomical Society. Additional co-authors are: W. Enzi, S. Vegetti and G. Despali, Max Planck Institute for Astrophysics, Garching, Germany; M.W. Auger, Institute of Astronomy, University of Cambridge, U.K.; L.V.E. Koopmans,Kapteyn Astronomical Institute, University of Groningen, The Netherlands; and J.P. McKean,Netherlands Institute for Radio Astronomy. The work was supported by the National Science Foundation, the Netherlands Organization for Scientific Research and the Chinese Academy of Sciences.

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Taking the Temperature of Dark Matter - UC Davis

The Milky Way Galaxy contains billions of massive bright stars. These high-mass stars have masses ranging from tens to hundreds of times the mass of the Sun. Their existence plays a role which is paramount in astrophysics.

They end their lives as supernovae which dramatically influences their environment. Yet, how they form still remains a mystery. The best current theories predict an upper limit of only about eight times the mass of the Sun.

For these stars, this leads to a discrepancy between theory and observation, which resulted in several competing theories emerging to explain this. One prominent emerging theory proposes that high-mass stars achieve their final mass from bursts of episodic accretion onto the protostar to achieve its final mass.

This theory predicts short-lived, intense accretion bursts through which the protostar gains mass from its surrounding accretion-disk, followed by long periods of inactivity, possibly lasting hundreds to thousands of years. In January 2019, astronomers at Ibaraki University in Japan noticed that one such massive protostar, G358-MM1, showed signs of new activity indicative of a potential accretion burst.

In response, a collaboration of astronomers, the Maser Monitoring Organization (M2O), gathered several radio telescopes from Australia, New Zealand and South Africa (HartRAO) to form a telescope array capable of detecting small-scale emission stimulated by the heat of the accreting protostar.

The team, led by Dr Ross Burns (NAOJ and JIVE), compared multiple images over the span of a month which revealed a heat-wave of energy radiating outward from the location of G358-MM1. According to Dr Fanie van den Heever (HartRAO/SARAO, South Africa), the observations made by M2O is the first real-time evidence supporting the episodic accretion theory for high-mass star formation.

The global community of astronomers, astrophysicists and theoreticians are benefiting tremendously from the work done by M2O and the recent results obtained by this group. The paper was published in Nature Astronomy on Monday, 13 January 2020.

About the authors

The work is led by Dr Ross Burns in collaboration with other M2O members. Dr Burns is affiliated to the National Astronomical Observatory of Japan (NAOJ) and the Joint Institute for VLBI in Europe (JIVE).

The South African contributors include:

Credit to Katharina Immer, affiliated with JIVE, for the artists impression.

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Astronomers Detect Radiation Stimulated By Heatwave Of Intense Thermal Energy From A Massive New-born Star - Space in Africa

A new study by a group of researchers at the University of Birmingham has found that collisions of supermassive black holes may be simultaneously observable in both gravitational waves and X-rays at the beginning of the next decade.

The European Space Agency (ESA) has recently announced that its two major space observatories of the 2030s will have their launches timed for simultaneous use. These missions, Athena, the next generation X-ray space telescope and LISA, the first space-based gravitational wave observatory, will be coordinated to begin observing within a year of each other and are likely to have at least four years of overlapping science operations.

According to the new study, published this week in Nature Astronomy, ESAs decision will give astronomers an unprecedented opportunity to produce multi-messenger maps of some of the most violent cosmic events in the Universe, which have not been observed so far and which lie at the heart of long-standing mysteries surrounding the evolution of the Universe.

They include the collision of supermassive black holes in the core of galaxies in the distant universe and the swallowing up of stellar compact objects such as neutron stars and black holes by massive black holes harbored in the centers of most galaxies.

The gravitational waves measured by LISA will pinpoint the ripples of space time that the mergers cause while the X-rays observed with Athena reveal the hot and highly energetic physical processes in that environment. Combining these two messengers to observe the same phenomenon in these systems would bring a huge leap in our understanding of how massive black holes and galaxies co-evolve, how massive black holes grow their mass and accrete, and the role of gas around these black holes.

These are some of the big unanswered questions in astrophysics that have puzzled scientists for decades.

Dr. Sean McGee, Lecturer in Astrophysics at the University of Birmingham and a member of both the Athena and LISA consortiums, led the study. He said, The prospect of simultaneous observations of these events is uncharted territory, and could lead to huge advances. This promises to be a revolution in our understanding of supermassive black holes and how they growth within galaxies.

Professor Alberto Vecchio, Director of the Institute for Gravitational Wave Astronomy, University of Birmingham, and a co-author on the study, said: I have worked on LISA for twenty years and the prospect of combining forces with the most powerful X-ray eyes ever designed to look right at the center of galaxies promises to make this long haul even more rewarding. It is difficult to predict exactly what were going to discover: we should just buckle up, because it is going to be quite a ride.

During the life of the missions, there may be as many as 10 mergers of black holes with masses of 100,000 to 10,000,000 times the mass of the sun that have signals strong enough to be observed by both observatories. Although due to our current lack of understanding of the physics occurring during these mergers and how frequently they occur, the observatories could observe many more or many fewer of these events. Indeed, these are questions which will be answered by the observations.

In addition, LISA will detect the early stages of stellar mass black holes mergers which will conclude with the detection in ground based gravitational wave observatories. This early detection will allow Athena to be observing the binary location at the precise moment the merger will occur.

Reference: Linking gravitational waves and X-ray phenomena with joint LISA and Athena observations by Sean McGee, Alberto Sesana and Alberto Vecchio, 6 January 2020, Nature Astronomy.DOI: 10.1038/s41550-019-0969-7

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Massive Black Hole Collisions Illuminated by X-Rays and Gravitational Waves - SciTechDaily

A new 3D movie highlights the Crab Nebula, beginning with its location in the constellation Taurus and zooming in to show off its dynamic features.

Data from the Hubble Space Telescope, Spitzer Space Telescope and the Chandra X-ray Observatory allowed visualists to piece together the different processes occurring in the beautiful structure.

Viewers of the four-minute video get a glimpse of the pulsing, super-dense stellar corpse within the Crab Nebula. This pulsar, or rapidly-spinning neutron star, blasts out radiation with clockwork precision about 30 times per second, NASA officials said in a statement.

The video was unveiled Jan. 5 at the 235th meeting of the American Astronomical Society in Honolulu, Hawaii.

Video: Crab Nebula visualized using NASA's 'Great Observatories' dataRelated: Amazing views of the famous Crab Nebula

This video isn't just a treat for the eyes it also helps scientists gain a fuller understanding about the Crab Nebula's world.

"Seeing two-dimensional images of an object, especially of a complex structure like the Crab Nebula, doesn't give you a good idea of its three-dimensional nature," said Frank Summers, visualization scientist from the Space Telescope Science Institute (STScI) in Baltimore, Maryland, in the statement. His team developed the movie.

"With this scientific interpretation, we want to help people understand the Crab Nebula's nested and interconnected geometry. The interplay of the multiwavelength observations illuminate all of these structures. Without combining X-ray, infrared and visible light, you don't get the full picture."

"Multiwavelength" means that Hubble, Spitzer and Chandra view different types of activity with their instruments, which are each fine-tuned to different wavelengths on the electromagnetic spectrum, explained NASA.

The pulsar at the center of the Crab Nebula contains certain structures and processes that generate particular wavelengths of light. That's why 3D movies like this one are as helpful as they are fun to watch.

Related: Cosmic Bat Nebula Photographed by ESO's Very Large Telescope

The visualization is from a new generation of products being created by NASA's Universe of Learning Program, an effort to connect scientific work with lay audiences. This particular video aims to highlight the reasons behind observing space through different wavelengths.

The Infrared Processing and Analysis Center (IPAC) at Caltech in Pasadena, California, and the Center for Astrophysics in Cambridge, Massachusetts, also helped produce the video.

Amateur astronomers can get their own good view of the Crab Nebula in January, Hubble officials said. The object was bright enough for 18th century technology to discover it, and astronomer Charles Messier even mistook the nebula for Halley's Comet. That's why the Crab Nebula is also known as Messier 1 (M1).

More importantly, the supernova that created the nebula wowed societies across the planet when it appeared in Earth's skies centuries ago. Chinese astronomers made a record of the "guest star" appearance in 1054. The supernova was visible in the daytime sky for about a month, according to NASA; it wasn't until the 20th century that astronomers realized that both M1 and the historic supernova were the same object.

As unique as this celestial object already is from humanity's perspective, the Crab Nebula is even more peculiar than your run-of-the-mill supernova. Hubble officials shared in the video description that the object is a pulsar-wind nebula.

A traditional nebula has a blast wave that scorches material around it, but the gas and dust in a pulsar wind nebula is heated by radiation to a lower temperature.

The use of many instruments is allowing researchers to wrap their heads around this special stellar corpse.

"It is truly via the multiwavelength structure that you can more cleanly comprehend that it's a pulsar wind nebula," Summers added in the statement. "This is an important learning objective. You can understand the energy from the pulsar at the core moving out to the synchrotron cloud, and then further out to the filaments of the cage."

Follow Doris Elin Urrutia on Twitter @salazar_elin. Follow us on Twitter @Spacedotcom and on Facebook.

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Tour the colorful Crab Nebula with this stunning new 3D visualization - Space.com