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

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

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

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

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

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

Space is the place for impossible molecules – The Week Magazine

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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

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

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

Taking the Temperature of Dark Matter – UC Davis

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

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

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

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

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

The Week of January 13, 2020 – FYI: Science Policy News

Brookhaven National Lab Picked as Electron-Ion Collider Site

The Department of Energy announced on Jan. 9 that it has selected Brookhaven National Laboratory as the site for the Electron-Ion Collider, a proposed nuclear science facility that the department estimates will cost between $1.6 billion and $2.6 billion. Brookhavens proposal for the collider calls for it to be built as a modification of the labs existing Relativistic Heavy Ion Collider. DOE granted the project initial approval on Dec. 19 and plans will be further developed over a period of years before the final go-ahead is ultimately given to begin construction. Provided Congress appropriates the needed funding, the department estimates the collider will take about a decade to design and build. The project was originally recommended in the 2015 Long Range Plan for Nuclear Science, and a 2018 National Academies report endorsed its scientific value. The only other contender to host the collider was the Thomas Jefferson National Accelerator Facility in Virginia, which would have built it as an extension of its Continuous Electron Beam Accelerator Facility. According to DOE, Jefferson Lab will still be a major partner as the project moves forward.

On Jan. 10, the Department of Energy released its solicitation of proposals for the Quantum Information Science Research Centers called for in the National Quantum Initiative Act. The department states it expects to award up to five centers, which together will receive up to $625 million in funding over a period of five years. Final proposals are due April 10 and are to describe multi-institutional collaborations that employ multi-disciplinary teams and blend together basic research, engineering, and technology development. The National Science Foundation has already initiated its process for awarding a counterpart set of QIS centers.

The Department of Energy announced on Jan. 8 that it is launching an Energy Storage Grand Challenge initiative that aims to accelerate the development, commercialization, and utilization of next-generation energy storage technologies. The effort will comprise R&D funding opportunities, prizes, and partnerships, among other components, with the objective of sustaining American leadership in the field and securing a manufacturing supply chain that is independent of foreign sources of critical materials by 2030. DOE will manage the challenge through the Research and Technology Investment Committee it established early last year and plans to release a request for information to obtain stakeholder feedback on what specific issues the challenge should address.

Last week, the National Academies Space Studies Board released the statement of task for the upcoming planetary science and astrobiology decadal survey, which will set the fields priorities for the years 2023 through 2032. While the survey will follow its predecessors in focusing on robotic missions to other planetary bodies, its additional focus on astrobiology is new and will encompass not only the search for life in the Solar System but also aspects of exoplanet research and the search for technosignatures of extraterrestrial intelligence. In addition, the survey will cover planetary defense, including both the scientific study of near-Earth objects and, for the first time, the hazards they present to Earth. Another new feature of the survey will be its consideration of planetary science opportunities involving crewed space missions, which has become a more important issue in light of NASAs expedited plans to return astronauts to the Moon. The state of the planetary science profession will also be on the agenda, following in the footsteps of the astronomy and astrophysics decadal survey due for release about a year from now. According to the planetary science surveys notional schedule, it will start accepting white papers from the research community next month and its leadership will be announced at the annual Lunar and Planetary Science Conference in March.

Update (1/14/2020): The National Academies has temporarily removed the statement of task from its website pending potential revisions.

The House Science Committee announced on Jan. 9 that Rep. Lizzie Fletcher (D-TX) has taken over as Energy Subcommittee chair from Rep. Conor Lamb (D-PA). Lamb, who remains on the subcommittee, stepped aside after joining the House Transportation and Infrastructure Committee late last year. In turn, Rep. Mikie Sherrill (D-NJ) is taking over Fletchers previous role as chair of the Environment Subcommittee and giving up her job as Investigations and Oversight Subcommittee chair. That spot will be filled by committee member Rep. Bill Foster (D-IL), who was a physicist at Fermilab before joining Congress in 2008.

The House Science Committee approved the Promoting Research and Observations of Space Weather to Improve the Forecasting of Tomorrow (PROSWIFT) Act by voice vote on Jan. 9. The bill, which is sponsored by Reps. Ed Perlmutter (D-CO) and Mo Brooks (R-AL), is similar to the Senates Space Weather Research and Forecasting Act, which the Senate Commerce, Science, and Transportation Committee advanced last April. However, before the committee approved the bill, it adopted an amendment introduced by Ranking Member Frank Lucas (R-OK), which would require the National Oceanic and Atmospheric Administration to establish a pilot program for obtaining space weather data from the commercial sector. Noting the program would expire after four years, Lucas said his amendment balances the need to help ensure there is a market for a commercial space weather data with the existing roles of the federal government and the academic community. A similar provision appeared in a previous version of the legislation that the committee advanced in 2018.

On Jan. 8, Democrats on the House Energy and Commerce Committee released adraft framework for climate legislation that sets an overarching goal of achieving a 100 percent clean economy by 2050, defined as reaching net-zero greenhouse gas emissions. Titled the Climate Leadership and Environmental Action for our Nations (CLEAN) Future Act, the draft bill will include provisions covering the power, building, transportation, and industrial sectors as well as a focus on clean energy workforce development. Beyond setting various renewable power and emissions standards, the bill will feature several R&D-oriented provisions. These include creating an Assistant Secretary for Manufacturing and Industry at DOE who would coordinate the agencys industrial efficiency initiatives, establishing a technology commercialization program for carbon capture and utilization, and creating a prize competition for direct air capture. The draft framework notes the committee plans to add provisions covering climate resilience, community transition, agriculture, financial issues, and international cooperation, among other areas. The committee expectsto release the text of the draft legislation by the end of the month.

Last week, the White House released a draft memorandum with guidance for federal agencies on how to approach the regulation and oversight of technologies that use artificial intelligence. The memorandum is a component of the Trump administrations AI initiative, which has been one of the Office of Science and Technology Policys foremost priorities. It instructs agencies to avoid adopting unnecessarily precautionary approaches and enumerates 10 principles they should consider when weighing the costs and benefits of potential regulations. U.S. Chief Technology Officer Michael Kratsios stated in an op-ed that the principles represent a light-touch approach to regulating AI that also aims to protect privacy and promote civil rights, civil liberties, and American values. The memorandum also provides examples of ways agencies can reduce barriers to the deployment and use of AI, such as increasing public access to federal data and models. Areas that are defined as falling outside the memorandums scope include the governments own use of AI technologies and the regulation of far-afield AI technologies that could approximate human intelligence.

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The Week of January 13, 2020 - FYI: Science Policy News

A Mysterious Burst of Gravitational Waves Came From a Region Near Betelgeuse. But There’s Probably No Connection – Universe Today

Gravitational waves are caused by calamitous events in the Universe. Neutron stars that finally merge after circling each other for a long time can create them, and so can two black holes that collide with each other. But sometimes theres a burst of gravitational waves that doesnt have a clear cause.

One such burst was detected by LIGO/VIRGO on January 14th, and it came from the same region of sky that hosts the star Betelgeuse. Yeah, Betelgeuse, aka Alpha Orionis. The star that has been exhibiting some dimming behaviour recently, and is expected to go supernova at some point in the future. Might the two be connected?

Betelgeuse is a red supergiant star in the constellation Orion. It left the main sequence about one million years ago and has been a red supergiant for about 40,000 years. Eventually, Betelgeuse will have burned enough of its hydrogen that its core will collapse, and it will explode as a supernova.

Recently, Betelgeuse dimmed. That set off all kinds of speculation that it might be getting ready to go supernova. Astrophysicists quickly poured water on that idea. Theres no exact number, but its estimated that Betelgeuse wont go supernova for another 100,000 years. But when a star dims, theres clearly something going on.

Is this new burst of gravitational waves connected to Betelgeuses recent dimming? To its future supernova explosion?

Astronomers understand that Betelgeuse is a variable star, and its brightness can fluctuate. Stars like Betelgeuse arent just static entities. Its a semi-regular variable star that shows both periodic and non-periodic changes in its brightness.

The kind of gravitational waves that LIGO detected are called burst waves. Its possible that a supernova could produce them, but Betelgeuse hasnt gone supernova and wont for a long time.

Some think that the detection of gravitational waves in Betelgeuses direction is unrelated to the star itself. In fact, the detection of the burst waves may not have even been real.

Christopher Berry is an astrophysicist studying gravitational waves at Northwestern Universitys Center for Interdisciplinary Exploration and Research in Astrophysics. On Twitter he spoke up about the gravitational burst waves.

Andy Howell from Las Cumbres Observatory studies supernova and dark energy. He had something to say on Twitter too, and appeared to be having fun with the whole thing. He even walked outside to check up on Betelgeuse after the detection of the burst gravitational waves.

So there you have it. No supernova for now, anyway. The burst gravitational waves may just be a glitch, and Betelgeuses dimming is well-understood and not a threat.

One day Betelgeuse will explode, and our night sky will change forever. But for us here on Earth, that supernova poses no problem.

An exploding star is an awesome event. And it produces a cataclysm of deadly radiation. X-rays, ultraviolet radiation, and even stellar material are ejected with great force. The deadliest radiation is gamma rays, and Betelgeuse likely wont even produce any of those when it blows.

But in any case, were about 700 light years away from Betelgeuse, and thats way too much distance for us to worry.

The biggest fallout is that the Orion constellation will change forever. And therell be a new object to study in the sky: a supernova remnant.

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A Mysterious Burst of Gravitational Waves Came From a Region Near Betelgeuse. But There's Probably No Connection - Universe Today

Scientific Discovery About the Source of a Key Element of Life Shows Why Sun Worship Is the Most Rational Religion – TheStranger.com

A gas and dust cloud in space... NASA

From Kathrin Altwegg, a member of the research team:

Upon reading about this finding, I recalled many things, one of which was the recent experience of listening to white Christian pop in a New York City bar.

The bar in question is called Forlini's. It's said to be very old and all that. It's comfortable enough. The tuna salad sandwich offered on its menu isn't half bad. But for a reason I could not determine, the bartender (or the owner of the business) chained the bar's radio to a station that played white Christian pop. As I ate and drank white wine, I listened to singer after singer go on and on about a Jesus who can only be described as totalitarian. He made us. He wants all of us.

One singer tried to escape His love but the poor fellow couldn't, and he was eternally thankful that he could not. Another singer claimed that she knew no one else in the whole wide world who was better, more perfect, more amazing than Him. And she was forever grateful for finding and becoming at one with the GOAT. In the throat of another, every atom was used to tell all who could hear that their life had no meaning whatsoever until they totally submitted to His infinite power. There was not a single song on the radio about Jesus's profoundly social message: helping those in need, not judging sinners, loving strangers as you love your family. None of that kind of thing. These singers had one story to tell: He/she was nothing until he/she submitted to the total power of the universe, the son of God.

But if we are to ignore Jesus' social message (a message I totally agree with), and only want to praise an elemental power, a force that is inescapable and fundamental to life itself, it seems to make no sense to sing about the supremacy of Jesus, a political figure (he was crucified not with thieves, but with men who were like him, rebels of the Roman state). These white Christian pop singers should instead be sun worshippers. Their songs are really about the stars, which, as one physicist put it, died (supernova) so that we could be born. Theirs is not the passion of Matthew but Atenism, the religion of ancient Egypt.

From Wikipedia:

The rays of the sun, its brilliant power, its connection with other stars, some of which generated phosphorus during their formation, and others ejected the stuff (the forces) of life across space during an explosion triggered by the final stage of nuclear fusion, iron. The praise songs on the Christian radio station were not about the complexities of social organization, or the struggles of the poor, but the elemental forces of life. That's not what Jesus is about, sorry. That wasn't his racket during his brief "time pan ert." He also, to his credit, didn't care much for miracles. If the primal is what you really want to worship, then turn to the sun and all of those "dishevelled wandering stars."

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Scientific Discovery About the Source of a Key Element of Life Shows Why Sun Worship Is the Most Rational Religion - TheStranger.com

Weekly Round-Up Of Space And Astronomy Opportunities For Africans – Space in Africa

Our Friday weekly round-up curates opportunities that are still open for application. The Opportunities portalaggregates job vacancies, internships, scholarships, calls for abstracts, fellowships, contests, exchange programmes and other opportunities that are available to Africans who are interested in space science and technology. Simply put, its an aggregator for space and astronomy-related opportunities for Africans.

Have you missed any opportunities this week? Check out the weekly round-up below.

Copernicus Master In Digital Earth Extends Application Deadline

Application deadline for Copernicus Master in Digital Earth has been extended till the 20th of January, 2020. Applications from European and International Candidates with a Geospatial background are welcome.

The African Union-led Global Monitoring for Environment and Security and Africa (GMES and Africa) Programme uses Copernicus Satellite data and information for the management of land and marine-based resources in Africa. The GMES and Africa Programme encourage interested African Earth Observation experts to apply for the Copernicus Masters on Digital Earth scholarship.

Erasmus+ EMJMD scholarships are available for European and international students. 17 scholarships will be available for this intake (6 Programme Countries = EU, 11 Partner Countries). A maximum of 30 students will start their studies on Copernicus Master in Digital Earth starting from October 2020. Scholarship awarded students are expected to arrive at the University of Salzburg, in Salzburg, Austria is Mid-September 2020.

Apply To Participate in The Open Geospatial Consortiums Testbed-16 Innovation

The Open Geospatial Consortium (OGC) is calling for participation in its next major Innovation Initiative, Testbed-16.Testbed-16 will address some of the hottest geospatial IT topics of this new decade: Earth Observation Clouds; Data Integration, Interoperability & Analytics; Data Containers; and Security.

OGC Testbeds, an annual activity ofOGCs Innovation Program, is a fast-paced, multi-vendor, collaborative effort where participants follow a rapid prototyping approach to design, develop, and test solutions to sponsors location-related problems. OGC Testbeds give room for research and new ideas, while also exploring the fitness for use of existing standards and solutions.

OGC Testbed results, in the form ofEngineering Reports, are provided toOGCs Standards Program, where they are reviewed, revised, and potentially advanced as new international open standards. Organizations participating in Testbeds, therefore, gain a first to market competitive advantage and early first-hand knowledge of the latest industry standards.

Each year, OGC Testbeds integrate requirements and ideas from a number of different sponsors. This pooling of ideas and requirements creates several symbiotic effects. In response to these ideas and requirements, Testbed-16 will address the following topics:

Funding is available to offset the cost of participation.

Deadline: The CFP submission deadline is February 9, 2020. The project will start with a kick-off meeting scheduled for early April 2020.

Click Apply To Participate in The Open Geospatial Consortiums Testbed-16 Innovation to apply and get further information

Scholarships Available For New Generation of Global STEM Leaders

AFS and BP are expanding their partnership to include India, along with Brazil, Egypt, and the USA as a host of theBP Global STEM Academies, the four-week scholarship programs focusing on science, technology, engineering, and math (STEM) and global competence education. This is the third year that this extraordinary, full scholarship study abroad program for students and active global citizens who are energized to help solve some of todays biggest global challenges.

Scholarship winners will enrich their STEM knowledge and skills through an interactive, hands-on curriculum, while developing critical global competencies, including problem-solving, analytical skills, intercultural understanding, and the ability to build bridges across cultures. The program culminates with team projects that offer potential solutions to real-world challenges, with an emphasis on climate change and the energy transition.

STEM programs like this are urgently needed as theyhelp young people develop innovative solutions to global issues, understand multiple STEM concepts, and comfortably thrive in a diverse workforce. The Academies leverage BPs deep expertise in STEM and AFSs established track record in international education to develop the next generation of globally competent leaders, making this a high-demand program.

AFS is proud that10 additional scholarships will be awarded to teens from Ghana, who will participate in the program for the first time this year. Another exciting development is theaddition of India as a new destination for one of the Academies. Participants from Brazil, China, Egypt, Germany, Ghana, India, Mexico, South Africa, and the USA are eligible to apply for the 2020 Academies.

The Academies are designed to ensure that the STEM community is inclusive for all teens of all backgrounds cultural, economic, etc. such that international education opportunities are open to those who may not be able to afford to go abroad.The BP Global STEM Academy scholarships cover the full participation fee, transportation and living costs of all attendees.

Deadline:Applications are open until 9 March 2020.

Click Scholarships Available For New Generation of Global STEM Leaders to apply and get further information

Apply To Participate in IAC 2020 Next Generation Plenary Proposal

This year, the Next Generation Plenary will focus on how students and young professionals are participating in Public/Private Partnerships (PPP) to inspire and innovate for the next generation. Public/Private Partnerships are vital to the growing space economy and for the future of space exploration. Such partnerships are characterized by government organizations and private companies sharing cost, risk, and benefits of success. We want to know how you are participating in Public/Private Partnerships in your work or research.

Are you an entrepreneur whos taking advantage of Public/Private Partnerships to start an innovative new company in the space sector? Are you a student conducting research to discover more about our universe or develop cutting edge technology? Perhaps youre a young professional working for a government agency or private company on a Public/Private Partnership and you want to share your unique perspective? We want to know how Public/Private Partnerships have enabled you to inspire and innovate for the next generation, and we encourage you to apply today!

You are invited to share your ideas in a plenary panel with an audience of senior space leaders in government, industry, and academia at the International Astronautical Congress inDubai 12-16 October 2020!

If approved by the IAF International Programme Committee (IPC), this event will take place during the week of 12-16 October 2020 in Dubai, at the International Astronautical Congress (IAC) (www.iac2020.org).

The participants will engage in a panel discussion with other students and young professionals from around the world and interact with the audience while discussing their efforts to inspire and innovate for and contribute to the Next Generation through Public/Private Partnerships. The plenary will be moderated in a format similar to a talk show, interweaving clips from the panellists audition videos with questions and comments from the moderator, other panellists, and the audience.

The video clips will be used to enhance the audiences understanding of the ideas of the plenary participants. This is an exciting opportunity that you do not want to miss!

To apply, you must be a student or young professional, aged from 21 to 35 years old on 1st January 2020.

Click Apply To Participate in IAC 2020 Next Generation Plenary Proposal to apply and get further information

Postdoctoral Fellowship Opportunity Available at the University of Cape Town, HEPCAT Group

The High Energy Physics, Cosmology & Astrophysics Theory (HEPCAT) group in the Department of Mathematics and Applied Mathematics at the University of Cape Town (UCT) is offering a SARChI in Physical Cosmology postdoctoral fellowship starting in 2020 with Prof. Amanda Weltman.

The position is funded by the South African Research Chairs Initiative (SARChI) of the National Research Foundation. The research priorities of this position are on the science of the HIRAX experiment and the MeerKAT telescope, specifically cosmological parameter estimations with BAOs, understanding Fast Radio Bursts (FRBs) and the cosmological implications of FRBs and using machine learning in astrophysics.

Applicants will use in-depth subject matter knowledge of radio pulsar and/or FRB astronomy to enable and deliver high-quality scientific publications from the MeerKAT telescope. In addition to the scientific exploitation of the sensitivity and capabilities of the MeerKAT and MeerLICHT telescopes, you will also have the opportunity to leverage other world-class multi-wavelength facilities for FRB science and cosmology. You will have the possibility to collaborate with the HIRAX team and the MeerTRAP team at the University of Manchester and this may involve regular travel between these institutes.

Applicants must have a track record of accomplishment and independence in their research. See more information on the activities of theHEPCAT group.

Deadline: February 16th, 2020.

Click Postdoctoral Fellowship Opportunity Available at the University of Cape Town, HEPCAT Group to apply and get further information

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Weekly Round-Up Of Space And Astronomy Opportunities For Africans - Space in Africa

What’s the temperature of dark matter? – Futurity: Research News

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Physicists 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 the University of California, 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 says. 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 says, but doesnt work so well on the scale of individual galaxies. Thats led to other models including warm dark matter with lighter, faster-moving particles. Observations have ruled out hot dark matter with particles moving close to the speed of light.

The researchers 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. Then the team 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 says.

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

The results put a lower limit on the mass of a potential dark matter particle while not ruling out cold dark matter, he says. 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 says.

A paper on the work appears in the Monthly Notices of the Royal Astronomical Society. Additional coauthors are from UC Davis; the Max Planck Institute for Astrophysics, Garching, Germany; the Institute of Astronomy, University of Cambridge, UK; the Kapteyn Astronomical Institute, University of Groningen, The Netherlands; and the Netherlands Institute for Radio Astronomy.

The National Science Foundation, the Netherlands Organization for Scientific Research, and the Chinese Academy of Sciences supported the work.

Source: UC Davis

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What's the temperature of dark matter? - Futurity: Research News

Researchers Have Identified 100 Mysteriously Disappeared Stars in The Night Sky – ScienceAlert

Across the Milky Way there are vacant spaces where a star once brightly shone. Some left clues in a dramatic death, or faded into retirement. Others simply moved into a new neighbourhood.

Not all vacancies have such convenient explanations, though. Some were there one moment and gone the next, inviting speculation over rare types of star death, extreme astrophysics, and, of course advanced alien technology.

By comparing star catalogues dating back to the 1950s with more recent datasets, researchers with the Vanishing & Appearing Sources during a Century of Observations project have identified around 100 bright dots that seem to have vanished without a trace.

The search is an ongoing one for lead researcher Beatriz Villarroel and her colleagues, one that started several years ago as part of a hunt for potential signs of alien intelligence.

"Finding an actually vanishing star or a star that appears out of nowhere! would be a precious discovery and certainly would include new astrophysics beyond the one we know of today,"says Villarroel, a theoretical physicist from Stockholm University.

In an earlier study Villarroel and her team compared the positions of some 10 million objects recorded in the US Naval Observatory Catalogue (USNO) with their counterparts in the Sloan Digital Sky Survey (SDSS).

They were left with about 290,000 missing objects, most of which could easily be accounted for on closer inspection. Eventually they found a single star that genuinely seemed to have disappeared, and even that discovery came with lingering doubts.

It was an intriguing find, but hardly constituted compelling evidence of new kinds of astrophysics.

In this latest study they compared 600 million objects in the USNO catalogue with a collection put together by the University of Hawaii's Pan-STARR system.

The naval catalogue spans around 50 years of sky surveys, capturing details of the entire sky in five colours down to a visual magnitude of about 21.The cosmic objects in the Pan-STARR data release include slightly dimmer objects, down to a magnitude of roughly 23 as compared to the SDSS's 22.

Having more stars to compare means potentially more 'missing' stars, while capturing objects of a lower magnitude means making extra sure there's nothing sitting in the star's place.

The comparison revealed 151,193 candidates for missing stars. This number was whittled down to 23,667 possibilities by widening the search field, cutting away stars that seemed to have moved farther than expected.

That short list was visually inspected, excluding around 18,000 images that were messed up by flaws or artefacts. Lastly, the team removed images where the missing star was towards the edge of the field, just to reduce risk of any false positives.

One final sweep using yet another method for comparisons removed other possible flaws in data collection, or unclear results. That left 100 dark shadows where a star once shone.

When a star dies, it usually goes out with a bright shout as a super nova, or quietly fades into a softly glowing ember like a white dwarf. They don't tend to just stop shining.

There could be some clues in the fact that the pool of candidates were in general a little redder in colour than the typical USNO catalogue object, and were generally faster moving. Working it out will take further research.

"We are very excited about following up on the 100 red transients we have found," says Villarroel.

There are plenty of explanations that need exploring before we can be confident this represents anything exotic, something the team hopes to accomplish with citizen science projects.

One possibility is that the object occasionally flares enough to be seen before dimming again a few magnitudes. Another explanation although very unlikely is they're all just scratches after all, and never existed to begin with. It could also be a dull star we assumed was farther away and has just moved too far to be noticed.

A more exciting thought is that a few might be super-rare failed supernovas, forming black holes without the fireworks display. As cool as that would be, it's a stretch to think this would explain all of the observations.

If the disappeared stars turn out to be none of these things, we may need to entertain new physics.

"We believe that they are natural, if somewhat extreme, astrophysical sources," says Martin Lpez Corredoira from the Instituto de Astrofsica de Canarias in the Canary Islands.

There is that other explanation. The one we'd all like to be true, but can't take seriously until we have a lot more evidence:Aliens could be covering these stars up to absorb their light, converting it into useful energy before shedding it as low grade radiation. Or the initial flares might be short lived, intense signals from alien technology.

In moments like this, we can all let our imaginations run a little wild, even if the researchers are hesitant.

"But we are clear that none of these events have shown any direct signs of being ETI [extra terrestrial intelligence]," says Corredoira.

Which might just be what the aliens want us to think.

This research was published in the Astronomical Journal.

Continued here:

Researchers Have Identified 100 Mysteriously Disappeared Stars in The Night Sky - ScienceAlert

Mysteriously Disappearing Stars Lead to Theories of New Astrophysics and Alien Technologies – Interesting Engineering

Astrophysicists deal with unknown phenomena all the time. One such phenomenon is the case of mysteriously disappearing stars.

RELATED:7 WEIRD STARS THAT HAVE ASTRONOMERS SCRATCHING THEIR HEADS

Researchers with the "Vanishing & Appearing Sources during a Century of Observations" (VASCO) projecthave identified 100 such stars that once existed and then magically stopped. They did so by comparing catalogs from the 1950s to today's data sets.

"Finding an actually vanishing star - or a star that appears out of nowhere! - would be a precious discovery and certainly would include new astrophysics beyond the one we know of today", said project leader Beatriz Villarroel, Stockholm University and Instituto de Astrofsica de Canarias, Spain.

When stars die they either become white dwarfs or supernovas. Stars that don't fit in either of these categories are considered "impossible phenomenon" that could be attributed either to new astrophysics or to alien activity.

Out of 15% of the 150,000 candidate objects in the available data, the researchers have spotted approximately a hundred red transients. "We are very excited about following up on the 100 red transients we have found", said Beatriz Villarroel.

Before you get too excited that these 100 objects may be due to alien activity it should be noted that the researchers discounted that possibility.

"But we are clear that none of these events have shown any direct signs of being ETI. We believe that they are natural, if somewhat extreme, astrophysical sources", said Martin Lpez Corredoira, co-author of the paper, Instituto de Astrofsica de Canarias, Spain.

Now, the researchers are seeking help to examine all150,000 candidate objects. Through acitizen science project, they hope to find more information on these anomalies. And who knows with a bit of luck they may actually detect some alien activity.

"We hope to get help from the community to look through the images as a part of a citizen science project," said Lars Mattsson, Stockholm University.

The rest is here:

Mysteriously Disappearing Stars Lead to Theories of New Astrophysics and Alien Technologies - Interesting Engineering

This drone will fly on one of Saturns moons. Heres the woman leading the mission – PBS NewsHour

A billion miles sounds impossibly far, but in planetary terms, You can get there, said Elizabeth Turtle.

In Turtles lifetime, shes seen human technology reach Uranus and Neptune, quick flybys that completely transformed our understanding of the solar system.

Thats why she is leading the hunt for rocks on Titan one of Saturns moons that, surprisingly, could tell us a lot about Earths early days.

Turtle who goes by the nickname Zibi is the principal investigator for NASAs Dragonfly mission, a drone-like vehicle the space agency plans to launch toward Titan in 2026.

The Dragonfly rotorcraft will finally arrive on Titan in 2034, after an eight-year-long voyage from Earth. During its 2.7 year-long baseline mission, it will take advantage of Titans dense atmosphere to travel more than 100 miles almost double the distance traveled by all of the land-based Mars rovers combined. By flying to multiple locations, the mission hopes to collect organic samples from a variety of environments.

Zibi Turtle. Photo by Johns Hopkins University Applied Physics Laboratory

Titan is one of the many satellites in the outer solar system with an interior water ocean, making it an ideal place to search for elements necessary for the origin of life. Its much colder than our planet, but is chemically similar to early Earth, Turtle said.

Humans have probed Titan in the past. In 2005, the European Space Agency landed on the moon during the Cassini mission, parachuting a camera toward the terrain that took photos during its two-and-a-half-hour descent. With Dragonfly, scientists hope to measure the chemical composition of the moons surface. Theyll look at how Titans atmosphere could affect those chemical compounds to get a better picture of which might be biologically relevant to the development of life.

In an interview with the PBS NewsHour, Turtle, who is also a planetary scientist, discussed the mission and what scientists are hoping to find. (Spoiler alert, it may not be aliens.)

The conversation has been edited for length and clarity.

Ive always been really interested in astronomy. My dad majored in astronomy. I kind of grew up going out to look at comets and meteor showers and aurora and things like that. Id always had an interest in college. I took a bunch of astrophysics courses and then I started taking planetary science courses. The planets are a little more closer and tangible, you can get there.

At the time, Voyager was making its way out to the Neptune and just the idea of exploration and the sense of how much we were learning in such a short period of time with these Uranus and Neptune flybys, was very quick. The New Horizons flyby took a very short period of time, and yet it completely transforms the understanding of the system.

Zibi Turtle is seen here in front of Yasur Volcano during a 2014 trip to observe and study volcanoes in Vanuatu, an archipelago about 1,000 miles east of Australia. Photo by Zibi Turtle

Its a very exciting field, theres just so much we dont know, and so many things that we have opportunities to learn.

I ended up going to grad school in planetary science and worked with the Galileo mission, studying Io and Europa, both moons of Jupiter. Then I worked with the Cassini mission, studying Titan primarily and some of the other icy satellites in the Saturnian system.

Titan is unique in that its the only moon in the solar system to have a dense atmosphere. This atmosphere is mostly nitrogen, like Earths atmosphere, and then it has methane as its next major constituent. Its so much colder in the outer solar system that the compositions are different, so you get very complex organic molecules. This complex organic matter has had the availability of liquid water in the past. You have all the ingredients we know to be necessary for life on the surface of Titan.

We want to study the pre-biotic chemistry the chemical steps that occurred that may have supported the development of life.

Dragonfly will take samples of Titans surface materials for chemical analysis. Image by NASA

Titan in many ways chemically is similar to early Earth, and so by studying Titan we can get an understanding of what processes may have happened here.

Instead of driving across the surface the way we often do on Mars, we fly from place to place with a rotorcraft. This gives us the ability to get to places over 100 kilometers apart and measure compositions in different environments with different histories.

In the past on Titan, liquid water would have been in contact with this organic material, meaning theres great opportunity for all of this pre-biotic organic synthesis to occur. We really want to understand the results of these chemistry experiments that Titan has been doing for millions of years. Then we want to put that in the context of Titan as a system.

Titan has a much thicker ice crust, but it has this organic material and thats really where the connection to the early Earth comes in.

Titan has a much thicker ice crust, but it has this organic material and thats really where the connection to the early Earth comes in. Its about the only place in the solar system that has this level of chemical complexity in terms of just the size of the carbon molecules on Titan, so its really the only the only parallel to Earth in terms of the chemistry available.

The other thing thats similar to the Earth is that because theres an atmosphere interacting with the surface, the geology is very similar. Not only do you have these similar molecules, but they have processes, like wind and rain, transporting them across the surface and mixing them the same way we have here on earth. There are lakes and seas on Titan of liquid methane instead of water here on earth, Titan being made of water ice instead of silicate rock here on Earth.

*Laughs*

We dont have reason to believe life would have developed on Titan. We cant say that it didnt, but its certainly not necessarily something wed expect. The surface temperature on Titan is 94 Kelvin, -290 Fahrenheit. Thats certainly not conducive to life as we know it. Everything is frozen solid at the surface.

We have the capability to make the measurements to detect chemical bio signatures, things like the chiral preferences for the structure of molecules. We do know that water and organic material have been in contact for long periods, but we dont know how long it took life to develop on Earth. We dont even know how long you need.

At this point, given the conditions there, we would be remiss if we didnt if we didnt look.

Hundreds of people are working on all of these projects and coming up with ways to solve challenges, to make things work better. Its a lot of fun. But its more fun when it works. Those are some of the less fun moments of mission or instrument design when you hit challenges that there isnt a way to surmount. Thats where things can be on the more frustrating side.

The exploration is incredibly fun. I remember as a grad student and postdoctoral researcher coming in to work at night when the new images from Galileo of Io were coming back, theres something different every time you look at it. It was spectacular to rush in and pull up the images and see what had happened, what volcanoes had started erupting since the previous flyby.

Zibi Turtle (bottom row, center) poses with the rest of the team from the Dragonfly mission. Image by NASA

That had this human desire to explore, to see whats behind beyond the horizon. This is just looking at all the ways of learning whats beyond the horizon further out in the solar system. Part of the excitement is really learning whats new and seeing what what we havent seen before on other planets and then trying to figure out how it works.

We went from barely knowing what the surface of Titan was like to understanding the geography of Titan, geological processes and how they fit together and how Titan works as a system. Its a huge privilege to be able to participate in that journey. And well be doing the same with the Europa Clipper and with Dragonfly.

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This drone will fly on one of Saturns moons. Heres the woman leading the mission - PBS NewsHour

Planetary Confusion Why Astronomers Keep Changing What It Means to Be A Planet – Space.com

This article was originally published atThe Conversation.The publication contributed the article to Space.com'sExpert Voices: Op-Ed & Insights.

Christopher Palma, Associate Dean for Undergraduate Students and Teaching Professor of Astronomy & Astrophysics, Pennsylvania State University

As an astronomer, the question I hear the most is why isn't Pluto a planet anymore? More than 10 years ago, astronomers famously voted to change Pluto's classification. But the question still comes up.

When I am asked directly if I think Pluto is a planet, I tell everyone my answer is no. It all goes back to the origin of the word "planet." It comes from the Greek phrase for "wandering stars." Back in ancient times before the telescope was invented, the mathematician and astronomer Claudius Ptolemy called stars "fixed stars" to distinguish them from the seven wanderers that move across the sky in a very specific way. These seven objects are the Sun, the Moon, Mercury, Venus, Mars, Jupiter and Saturn.

When people started using the word "planet," they were referring to those seven objects. Even Earth was not originally called a planet but the Sun and Moon were.

Since people use the word "planet" today to refer to many objects beyond the original seven, it's no surprise we argue about some of them.

Although I am trained as an astronomer and I studied more distant objects like stars and galaxies, I have an interest in the objects in our Solar System because I teach several classes on planetary science.

The word "planet" is used to describe Uranus and Neptune, which were discovered in 1781 and 1846 respectively, because they move in the same way that the other "wandering stars" move. Like Saturn and Jupiter, if you look at them through a telescope, they appear bigger than stars, so they were recognized to be more like planets than stars.

Not long after the discovery of Uranus, astronomers discovered additional wandering objects these were named Ceres, Pallas, Juno and Vesta. At the time they were considered planets, too. Through a telescope they look like pinpoints of light and not disks. With a small telescope, even distant Neptune appears fuzzier than a star. Even though these other, new objects were called planets at first, astronomers thought they needed a different name since they appear more star-like than planet-like.

William Herschel (who discovered Uranus) is often said to have named them "asteroids" which means "star-like," but recently, Clifford Cunningham claimed that the person who coined that name was Charles Burney Jr., a preeminent Greek scholar.

Today, just like the word "planet," we use the word "asteroid" differently. Now it refers to objects that are rocky in composition, mostly found between Mars and Jupiter, mostly irregularly shaped, smaller than planets, but bigger than meteoroids. Most people assume there is a strict definition for what makes an object an asteroid. But there isn't, just like there never was for the word "planet."

In the 1800s the large asteroids were called planets. Students at the time likely learned that the planets were Mercury, Venus, Earth, Mars, Ceres, Vesta, Pallas, Juno, Jupiter, Saturn, Uranus and, eventually, Neptune. Most books today write that asteroids are different than planets, but there is a debate among astronomers about whether the term "asteroid" was originally used to mean a small type of planet, rather than a different type of object altogether.

These days, scientists consider properties of these celestial objects to figure out whether an object is a planet or not. For example, you might say that shape is important; planets should be mostly spherical, while asteroids can be lumpy. As astronomers try to fix these definitions to make them more precise, we then create new problems. If we use roundness as an important distinction for objects, what should we call moons? Should moons be considered planets if they are round and asteroids if they are not round? Or are they somehow different from planets and asteroids altogether?

I would argue we should again look to how the word "moon" came to refer to objects that orbit planets.

When astronomers talk about the Moon of Earth, we capitalize the word "Moon" to indicate that it's a proper name. That is, the Earth's moon has the name, Moon. For much of human history, it was the only Moon known, so there was no need to have a word that referred to one celestial body orbiting another. This changed when Galileo discovered four large objects orbiting Jupiter. These are now called Io, Europa, Ganymede and Callisto, the moons of Jupiter.

This makes people think the technical definition of moon is a satellite of another object, and so we call lots of objects that orbit Mars, Jupiter, Saturn, Uranus, Neptune, Pluto, Eris, Makemake, Ida and a large number of other asteroids moons. When you start to look at the variety of moons, some, like Ganymede and Titan, are larger than Mercury. Some are similar in size to the object they orbit. Some are small and irregularly shaped, and some have odd orbits.

So they are not all just like Earth's Moon. If we try to fix the definition for what is a moon and how that differs from a planet and asteroid, we are likely going to have to reconsider the classification of some of these objects, too. You can argue that Titan has more properties in common with the planets than Pluto does, for example. You can also argue that every single particle in Saturn's rings is an individual moon, which would mean that Saturn has billions upon billions of moons.

The most recent naming challenge astronomers face arose when they discovering planets far from our Solar System orbiting around distant stars. These objects have been called extrasolar planets, exosolar planets or exoplanets.

Astronomers are currently searching for exomoons orbiting exoplanets. Exoplanets are being discovered that have properties unlike the planets in our Solar System, so astronomers have started putting them in categories like "hot Jupiter," "warm Jupiter," "super-Earth" and "mini-Neptune."

Ideas for how planets form also suggest that there are planetary objects that have been flung out of orbit from their parent star. This means there are free-floating planets not orbiting any star. Should planetary objects that are flung out of a solar system also get ejected from the elite club of planets?

When I teach, I end this discussion with a recommendation. Rather than arguing over planet, moon, asteroid and exoplanet, I think we need to do what Herschel and Burney did and coin a new word. For now, I use "world" in my class, but I do not offer a rigorous definition of what makes something a world and what does not. Instead, I tell my students that all of these objects are of interest to study.

A lot of people seem to feel that scientists wronged Pluto by changing its classification. I look at it that Pluto was only originally called a planet because of an accident; scientists were looking for planets beyond Neptune, and when they found Pluto they called it a planet, even though its observable properties should have led them to call it an asteroid.

As our understanding of this object has grown, I feel like the evidence now leads me to call Pluto something besides planet. There are other scientists who disagree, feeling Pluto still should be classified as a planet.

But remember: The Greeks started out calling the Sun a planet given how it moved on the sky. We now know that the properties of the Sun show it to belong in a very different category from the planets; it's a star, not a planet. If we can stop calling the Sun a planet, why can't we do the same to Pluto?

This article is republished fromThe Conversationunder a Creative Commons license. Read theoriginal article.

Follow all of the Expert Voices issues and debates and become part of the discussion on Facebook and Twitter. The views expressed are those of the author and do not necessarily reflect the views of the publisher.

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Planetary Confusion Why Astronomers Keep Changing What It Means to Be A Planet - Space.com

Year in Review: Milestones for Women in Space Through 2019 – News18

On April 10, 2019, a tweet went viral showing computer scientist Katie Bouman and her look of delightful surprise. Bouman was at the helm of the team that developed an algorithm that stitched together images to give the world a very first look at a black hole. The rest is history, still in the making.

Bouman, a graduate from the Massachusetts Institute of Technologys Computer Science and Artificial Intelligence Laboratory (MIT-CSAIL), is an assistant professor at the California Institute of Technology (Caltech). Boumans work with the Event Horizon Telescope team and her own CHIRP algorithm, which stands for Continuous High-resolution Image Reconstruction using Patch priors, was pivotal in the breakthrough that helped create the image of a black hole intergalactic dying stars that many scientists before her deemed impossible to photograph by virtue of their properties. Bouman and her team, had other ideas.

It is this that underlines the grand narrative of women and their roles in space research and astrophysics. The achievement solidified Bouman as a role model in a field that has been typically male dominated for long. Her work and achievements also pay homage to women in space, and their myriad contributions that have helped mankind understand science beyond the times.

NASA astronaut Christina Koch.

Boumans work came right on the back of NASA astronaut Christina Kochs arrival at the International Space Station (ISS). Soon after her arrival, NASA made a milestone announcement by extending Kochs stay aboard the ISS until February 2020. This scheduled her to officially become the longest woman resident in space, wherein she is set to clock 328 days in microgravity. Her stay will come mighty close to the 340 days that fellow NASA astronaut Scott Kelly spent at ISS, and her contribution will be instrumental in our understanding of the effects of long term spaceflight in near-zero gravity conditions.

In India, on July 22, the Indian Space Research Organisation (ISRO)s historic Chandrayaan-2 mission took off for the moon. While the mission did not complete its objective due to a part-mission failure with the Vikram lander, ISROs Chandrayaan-2 still played a crucial role in progressing Indias position in global space mission. At its helm were the Rocket Women of India, ISROs project director Muthayya Vanitha, and mission director, Ritu Karidhal. Their tumultuous contributions were a part of Mangalyaan Indias Mars mission, Chandrayaan, and Mission Shakti, Indias own anti-satellite missile test. Karidhal and Vanitha became the face of ISROs achievements while Karidhals 22-year stint at ISRO became widely recognised, Vanitha was named as one of the top five scientists to watch by Nature journal.

ISRO mission director Ritu Karidhal.

Back at NASA, Koch set more records later in 2019 when she, along with new ISS resident Jessica Meir, held the first ever all-female spacewalk on October 18. In her post-spacewalk broadcast back to Earth, Koch stated, We're in sort of a new chapter now where we've crossed that line and two women have done it. Now, hopefully, it will become commonplace and it won't even necessarily be something that's a big deal down the road.

Koch and Meirs contribution to our space research was the first of its kind, but aims to make it regular and natural for more women astronauts to follow. It is this that makes the contributions of Bouman, Koch, Meir and all other women in space research right now so important the ultimate goal, after all, is to not have any notion of gender bias around.

The women that made 2019 the year of women in space also pay homage to astrophysicists, engineers and researchers, dating all the way back to the first Apollo mission in 1969. While progress in this field has not been the fastest, it speaks volumes when one considers that during the iconic Apollo 11 mission, the only woman in the entire team was JoAnn H. Morgan, the only woman in the Apollo mission control room, and the first ever female engineer at NASAs Kennedy Space Center. For India, the image of women researchers celebrating post Chandrayaan-2s successful launch will inspire generations to come.

The trail blazed forth by these women have seen their impact already, in the form of NASA renaming the street in front of their Washington, DC headquarters to Hidden Figures Way in honour of Katherine Johnson, Dorothy Vaughan and Mary Jackson, women who were pivotal to achievements made in the first Space Race era. NASA further announced the Artemis moon mission for 2024, when the first ever woman is slated to set foot on the moon.

Going forward, 2019 will be remembered as the year when women led mankinds charge towards the unexplored frontiers, bringing mankind closer to reaching for the stars.

Get the best of News18 delivered to your inbox - subscribe to News18 Daybreak. Follow News18.com on Twitter, Instagram, Facebook, Telegram, TikTok and on YouTube, and stay in the know with what's happening in the world around you in real time.

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Year in Review: Milestones for Women in Space Through 2019 - News18

The billion-year belch – MIT News

Billions of years ago, in the center of a galaxy cluster far, far away (15 billion light-years, to be exact), a black hole spewed out jets of plasma. As the plasma rushed out of the black hole, it pushed away material, creating two large cavities 180 degrees from each other. In the same way you can calculate the energy of an asteroid impact by the size of its crater, Michael Calzadilla, a graduate student at the MIT Kavli Institute for Astrophysics and Space Research (MKI), used the size of these cavities to figure out the power of the black holes outburst.

In a recent paper in The Astrophysical Journal Letters, Calzadilla and his coauthors describe the outburst in galaxy cluster SPT-CLJ0528-5300, or SPT-0528 for short. Combining the volume and pressure of the displaced gas with the age of the two cavities, they were able to calculate the total energy of the outburst. At greater than 1054 joules of energy, a force equivalent to about 1038 nuclear bombs, this is the most powerful outburst reported in a distant galaxy cluster. Coauthors of the paper include MKI research scientist Matthew Bayliss and assistant professor of physics Michael McDonald.

The universe is dotted with galaxy clusters, collections of hundreds and even thousands of galaxies that are permeated with hot gas and dark matter. At the center of each cluster is a black hole, which goes through periods of feeding, where it gobbles up plasma from the cluster, followed by periods of explosive outburst, where it shoots out jets of plasma once it has reached its fill. This is an extreme case of the outburst phase, says Calzadilla of their observation of SPT-0528. Even though the outburst happened billions of years ago, before our solar system had even formed, it took around 6.7 billion years for light from the galaxy cluster to travel all the way to Chandra, NASAs X-ray emissions observatory that orbits Earth.

Because galaxy clusters are full of gas, early theories about them predicted that as the gas cooled, the clusters would see high rates of star formation, which need cool gas to form. However, these clusters are not as cool as predicted and, as such, werent producing new stars at the expected rate. Something was preventing the gas from fully cooling. The culprits were supermassive black holes, whose outbursts of plasma keep the gas in galaxy clusters too warm for rapid star formation.

The recorded outburst in SPT-0528 has another peculiarity that sets it apart from other black hole outbursts. Its unnecessarily large. Astronomers think of the process of gas cooling and hot gas release from black holes as an equilibrium that keeps the temperature in the galaxy cluster which hovers around 18 million degrees Fahrenheit stable. Its like a thermostat, says McDonald. The outburst in SPT-0528, however, is not at equilibrium.

According to Calzadilla, if you look at how much power is released as gas cools onto the black hole versus how much power is contained in the outburst, the outburst is vastly overdoing it. In McDonalds analogy, the outburst in SPT-0528 is a faulty thermostat. Its as if you cooled the air by 2 degrees, and thermostats response was to heat the room by 100 degrees, McDonald explains.

Earlier in 2019, McDonald and colleagues released a paper looking at a different galaxy cluster, one that displays a completely opposite behavior to that of SPT-0528. Instead of an unnecessarily violent outburst, the black hole in this cluster, dubbed Phoenix, isnt able to keep the gas from cooling. Unlike all the other known galaxy clusters, Phoenix is full of young star nurseries, which sets it apart from the majority of galaxy clusters.

With these two galaxy clusters, were really looking at the boundaries of what is possible at the two extremes, McDonald says of SPT-0528 and Phoenix. He and Calzadilla will also characterize the more normal galaxy clusters, in order to understand the evolution of galaxy clusters over cosmic time. To explore this, Calzadilla is characterizing 100 galaxy clusters.

The reason for characterizing such a large collection of galaxy clusters is because each telescope image is capturing the clusters at a specific moment in time, whereas their behaviors are happening over cosmic time. These clusters cover a range of distances and ages, allowing Calzadilla to investigate how the properties of clusters change over cosmic time. These are timescales that are much bigger than a human timescale or what we can observe, explains Calzadilla.

The research is similar to that of a paleontologist trying to reconstruct the evolution of an animal from a sparse fossil record. But, instead of bones, Calzadilla is studying galaxy clusters, ranging from SPT-0528 with its violent plasma outburst on one end to Phoenix with its rapid cooling on the other. Youre looking at different snapshots in time, says Calzadilla. If you build big enough samples of each of those snapshots, you can get a sense how a galaxy cluster evolves.

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The billion-year belch - MIT News

Astronomers discover a new exoplanet 66.5 light-years away, making it one of the nearest known to date – MEAWW

Every new planet found orbiting a distant star opens a world of possibilities for astronomers. And a team of scientists has now discovered a rocky exoplanet -- a little bigger than Earth -- which is among the smallest, nearest exoplanets known to date.

The exoplanet -- implying a planet outside our Solar System -- has been dubbed as GJ 1252 b. It is only 66.5 light-years away, orbiting a red dwarf star GJ 1252, according to researchers from the Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology; and Center for Astrophysics, Harvard & Smithsonian, among others.

Here we present the discovery of GJ 1252 b, a small planet orbiting an M dwarf. The planet was initially discovered as a transiting planet candidate using TESS (Transiting Exoplanet Survey Satellite) data. Based on the TESS data and additional follow-up data, we are able to reject all false positive scenarios, showing it is a real planet. In addition, we were able to obtain a marginal mass measurement, say the researchers in a pre-print version on arXiv, which is operated by Cornell University. The research has also been submitted to the American Astronomical Society.

The Solar System has either small, rocky planets like Earth, Mercury, Venus, and Mars, or much larger planets like Saturn, Jupiter, Uranus, and Neptune that are dominated by gases rather than land, say scientists. The discovery of exoplanets such as GJ 1252 b will enable scientists to better understand the worlds orbiting other stars, as well as study the missing link between rocky Earth-like planets and gas-dominant mini-Neptunes.

The diameter of our galaxy is 100,000 light-years, and our galaxy is just one of the millions of galaxies. So, 66.5 light-years imply that it is one of our neighboring stars, say experts. GJ 1252 was observed by camera 2 of the TESS spacecraft during Sector 13, from June 19, 2019, to July 17, 2019.

NASA describes TESS as the next step in the search for planets outside of our solar system, including those that could support life. TESS -- launched on April 18, 2018, aboard a SpaceX Falcon 9 rocket -- will survey 200,000 of the brightest stars near the sun to search for transiting exoplanets.

According to the scientists, GJ 1252 b joins a small but growing group of small planets orbiting nearby M dwarf stars. It also joins the group of small planets orbiting at very short periods, commonly called ultra-short periods, or USPs. Experts say that USPs orbital period ranges from about one day down to less than 10 hours, and even as short as about 4 hours, especially around M dwarfs. Planets in this group are believed to have undergone photo-evaporation which removed their atmosphere.

GJ 1252 b joins the short but growing list of small planets orbiting bright and nearby stars discovered by TESS that are amenable to detailed characterization. GJ 1252 is one of the closest planet host stars to the Sun to host a planet with a measured radius. GJ 1252s brightness and the short orbital period (0.518 day, or 12.4 hours) make it a potential target for transmission and emission spectroscopy, which can reveal whether or not the planet has an atmosphere, says the team.

The field of exoplanets has come a long way since the first discoveries at the end of the 20th century. One of the current frontiers in the study of exoplanets is that of small planets, smaller than Neptune and Uranus. However, the number of small planets with a well-measured mass is still small, say experts.

The study of small planets is hampered by the lack of small planets orbiting stars that are bright enough for detailed follow-up investigations. The TESS mission is designed to overcome this problem by detecting transiting planet candidates orbiting bright stars positioned across almost the entire sky. So far, 4,104 exoplanets have been confirmed in our galaxy.

Among those, planet candidates orbiting nearby M dwarf stars present a special opportunity, as their typical high proper motion and small size make it easier to rule out false-positive scenarios. This quickly clears the way for follow-up studies, including mass measurement and atmospheric characterization, says the study.

See more here:

Astronomers discover a new exoplanet 66.5 light-years away, making it one of the nearest known to date - MEAWW


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