The Milky Way, the galaxy we live in, is one of hundreds of billions of galaxies strewn across the universe. Their variety is stunning: spirals, ring galaxies shaped like star-studded loops, and ancient galaxies that outshine virtually everything else in the universe.

But despite their differences, and the mind-boggling distances between them, scientists have noticed that some galaxies move together in odd and often unexplained patterns, as if they are connected by a vast unseen force.

Galaxies within a few million light years of each other can gravitationally affect each other in predictable ways, but scientists have observed mysterious patterns between distant galaxies that transcend those local interactions.

These discoveries hint at the enigmatic influence of so-called large-scale structures which, as the name suggests, are the biggest known objects in the universe. These dim structures are made of hydrogen gas and dark matter and take the form of filaments, sheets, and knots that link galaxies in a vast network called the cosmic web. We know these structures have major implications for the evolution and movements of galaxies, but weve barely scratched the surface of the root dynamics driving them.

Scientists are eager to acquire these new details because some of these phenomena challenge the most fundamental ideas about the universe.

Thats actually the reason why everybody is always studying these large-scale structures, said Noam Libeskind, a cosmographer at the Leibniz-Institut for Astrophysics (AIP) in Germany, in a call. Its a way of probing and constraining the laws of gravity and the nature of matter, dark matter, dark energy, and the universe.

Why are distant galaxies moving in unison?

Galaxies tend to form gravitationally bound clusters that belong to even larger superclusters. Earths long-form cosmic address, for instance, would have to note that the Milky Way is part of the Local Group, a gang of several dozen galaxies. The Local Group is inside the Virgo supercluster, containing more than 1,000 galaxies.

On these more local scales, galaxies frequently mess with each others spins, shapes, and angular velocities. Sometimes, one galaxy even eats another, an event known as galactic cannibalism. But some galaxies show dynamic links across distances too great to be explained by their individual gravitational fields.

For instance, a study published in The Astrophysical Journal in October found that hundreds of galaxies were rotating in sync with the motions of galaxies that were tens of millions of light years away.

This discovery is quite new and unexpected, said lead author Joon Hyeop Lee, an astronomer at the Korea Astronomy and Space Science Institute, in an email. I have never seen any previous report of observations or any prediction from numerical simulations, exactly related to this phenomenon.

Lee and his colleagues studied 445 galaxies within 400 million light years of Earth, and noticed that many of the ones rotating in a direction toward Earth had neighbors that were moving toward Earth, while those that were rotating in the opposite direction had neighbors moving away from Earth.

The observed coherence must have some relationship with large-scale structures, because it is impossible that the galaxies separated by six megaparsecs [roughly 20 million light years] directly interact with each other, Lee said.

Lee and his colleagues suggest that the synchronized galaxies may be embedded along the same large-scale structure, which is very slowly rotating in a counter-clockwise direction. That underlying dynamic could cause the kind of coherence between the rotation of the studied galaxies and the motions of their neighbors, though he cautioned that it will take a lot more research to corroborate his teams findings and conclusions.

While this particular iteration of weirdly synced up galaxies is novel, scientists have observed odd coherences between galaxies at even more mind-boggling distances. In 2014, a team observed curious alignments of supermassive black holes at the cores of quasars, which are ancient ultra-luminous galaxies, that stretch across billions of light years.

Led by Damien Hutsemkers, an astronomer at the University of Lige in Belgium, the researchers were able to observe this eerie synchronicity by watching the universe when it was only a few billion years old, using the Very Large Telescope (VLT) in Chile. The observations recorded the polarization of light from nearly 100 quasars, which the team then used to reconstruct the geometry and alignment of the black holes at their cores. The results showed that the rotation axes of 19 quasars in this group were parallel, despite the fact that they were separated by several billion light years.

The discovery, which was published in the journal Astronomy & Astrophysics, is an indicator that large-scale structures influenced the dynamics of galaxies across vast distances in the early universe.

Galaxy spin axes are known to align with large-scale structures such as cosmic filaments but this occurs on smaller scales, Hutsemkers said in an email, noting that theoretical studies have proposed some tentative explanations of this process.

However, there is currently no explanation why the axes of quasars are aligned with the axis of the large group in which they are embedded, he noted.

The truth behind synchronized galaxies could change everything

The secret of these synchronized galaxies may pose a threat to the cosmological principle, one of the basic assumptions about the universe. This principle states that the universe is basically uniform and homogenous at extremely large scales. But the existence of correlations in quasar axes over such extreme scales would constitute a serious anomaly for the cosmological principle, as Hutsemkers and his colleagues note in their study.

However, Hutsemkers cautioned that more of these structures would need to be spotted and studied to prove that this is a serious wrinkle in the cosmological principle. Other similar structures are needed to confirm a real anomaly, he said.

For the moment, the dynamics behind these quasar positions are not well understood because there are few observational techniques to refine them. As far as large-scale alignments are concerned, we are essentially waiting for more data, Hutsemkers said. Such studies are statistical and a step forward would require a large amount of polarization data, not easy to gather with current instrumentation.

Future radio telescopes, such as the Square Kilometre Array, might be able to probe these mysterious alignments in more detail.

One of the great things about science is that you can have a model built with thousands of pieces of data but if one thing doesnt stick it starts to crack. That crack either has to be sealed or its going to bring the whole house down.

Quasar alignments are not the only hurdles that oddly synchronized galaxies have presented to established models of the universe. In fact, one of the most contentious debates in cosmology these days is centered around the unexpected way in which dwarf galaxies appear to become neatly aligned around larger host galaxies such as the Milky Way.

These satellite galaxies are currently a thorn in the side of what is known as the CDM model, which is a theoretical timeline of the universe since the Big Bang. Simulations of the universe under the CDM model predict that small satellite galaxies will end up in a swarm of random orbits around larger host galaxies.

But over the past decade, new observations have revealed that a huge chunk of the satellite galaxies around the Milky Way are synced up into one tidy orbital plane. At first, scientists wondered whether that simply meant something weird was going on with our own galaxy, but a similar plane of satellites was then observed around Andromeda.

The alarm bells really started ringing in 2015, when astronomers published observations of the same phenomenon a third time around Centaurus A, an elliptical galaxy about 10 million light years from the Milky Way.

This discovery suggests that something is wrong with standard cosmological simulations, according to a subsequent 2018 study in Science, led by Oliver Mller, an astronomer at the University of Strasbourg in France.

At the moment, we have observed this at the three closest galaxies, Mller said in a call. Of course, you can always say that its only three, so its not statistical yet. But it shows that every time we have good data, we find it, so it could be universal.

In a 2015 study, Libeskind and his colleagues suggested that filaments in the cosmic web might be guiding these organized galaxies, a process that could cohere with the CDM model. Ultimately, though, theres no conclusive answer to this dilemma yet.

One of the great things about science is that you can have a model built with thousands of pieces of data but if one thing doesnt stick it starts to crack, said Libeskind. That crack either has to be sealed or its going to bring the whole house down.

The next generation of galaxy research

This tantalizing uncertainty has motivated astronomers like Marcel Pawlowski, a Schwarzschild Fellow at AIP and co-author on the 2018 Science study, to make this problem a focus of their research. Pawlowski is looking forward to data from the next generation of huge 30-meter class observatories that could show whether other big galaxies are surrounded by either isotropic or organized patterns of satellite galaxies.

What we have to do now is expand our search to more distant satellite systems, and find satellite galaxies as well as measure their velocities, said Pawlowski in a call.

The field really advanced because of this debate going on in the literature, Pawlowski added. Its been really good to see how the observational evidence became more and more solid.

Whether its the strange motions of dwarf galaxies in our own galactic neighborhood or the eerie alignment of galaxies over millions or billions of light years, its clear that the dance moves of galaxies are an essential key to unlocking the large-scale structure of the universe.

The galaxies we see captured in static positions in beautiful deep-field shots are actually guided by many complex forces we dont yet fully comprehend, including the cosmic web that undergirds the universe.

What I really like about this stuff is just that we are still at the pioneering phase, said Mller. Thats super exciting.

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Theres Growing Evidence That the Universe Is Connected by Giant Structures - VICE

The Department of Energy has awarded Fermilab and University of Chicago scientist Josh Frieman $1 million over three years as part of the inaugural Office of Science Distinguished Scientist Fellowship program.

Office of Science distinguished scientist fellows were chosen from nominations submitted by nine U.S. national laboratories. Frieman is one of only five scientists selected, chosen for his scientific leadership, engagement with the academic research community, scientific excellence and significant scientific achievement.

The Distinguished Scientist Fellowship was established to develop, sustain and promote excellence in Office of Science research through collaborations between institutions of higher education and national laboratories.

Frieman says he will use the funding to support his cosmic research program and to foster tighter connections in cosmic frontier research between Fermilab and the University of Chicago.

While a significant number of University of Chicago graduate students and postdoctoral researchers have conducted research at Fermilab in a variety of areas of high-energy physics, very few currently carry out cosmology or theoretical astrophysics work at the lab.

Frieman aims to change that by building more active collaboration between Fermilab and the University of Chicago in research with cosmic surveys.

There are many very talented students at the university and many very talented scientists at Fermilab, Frieman said. Ive mentored students and postdocs at the University of Chicago, but few of them have spent time at Fermilab. And there are postdocs in the astrophysics groups at Fermilab who spend a small fraction of their time at the university. Im looking to bridge that gap, to help make the whole greater than the sum of its parts.

Friemans current research centers on the Fermilab-hosted Dark Energy Survey a project he led from 2010 to 2018 and will transition in coming years to the Large Synoptic Survey Telescope, whose construction is managed by SLAC National Accelerator Laboratory.

With its full data set accumulated, the Dark Energy Survey is at a very exciting phase of its science analysis, and both the university and Fermilab will play significant roles in LSST. Id like to get more students and postdocs engaged in both projects and to stimulate synergies between the lab and the university in the process, he said. Collaboration drives science forward, and this award recognizes that the more closely the labs and universities work together, the further we can take our research. Its an honor to be among the first recipients of this fellowship.

With a long list of leadership roles and academic distinctions to his credit, Frieman has the experience needed to bring these two research groups together. Currently the president of the Aspen Center for Physics, Frieman is a fellow of the American Physical Society, of the American Association for the Advancement of Science, and of the American Academy of Arts and Sciences. He is also chair of the American Physical Society Division of Astrophysics. He previously served on the Particle Physics Project Prioritization Panel of the High Energy Physics Advisory Panel, on the Astro 2010 Decadal Survey Committee, and on the Astronomy and Astrophysics Advisory Committee.

Frieman is head of the Fermilab Particle Physics Division and is a professor of astronomy and astrophysics and member of the Kavli Institute for Cosmological Physics at the University of Chicago.

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Fermilab and University of Chicago scientist Josh Frieman awarded $1 million by DOE Office of Science - Fermi National Accelerator Laboratory

Here's the reality: We're messing up the Earth and any far-out ideas of colonizing another orb when we're done with our own are wishful thinking. That's according to Michel Mayor, an astrophysicist who was a co-recipient of the Nobel Prize in physics this year for discovering the first planet orbiting a sun-like star outside of our solar system.

"If we are talking about exoplanets, things should be clear: We will not migrate there," he told Agence France-Presse (AFP). He said he felt the need to "kill all the statements that say, 'OK, we will go to a livable planet if one day life is not possible on Earth.'"

All of the known exoplanets, or planets outside of our solar system, are too far away to feasibly travel to, he said. "Even in the very optimistic case of a livable planet that is not too far, say a few dozen light years, which is not a lot, it's in the neighbourhood, the time to go there is considerable," he added.

Related: 8 Ways Global Warming Is Already Changing the World

Mayor shared half of the Nobel Prize this year along with Didier Queloz for discovering the first exoplanet in October 1995. Using novel instruments at the Haute-Provence Observatory in southern France, they detected a gas giant similar to Jupiter, which they named 51 Pegasi b. (The other half of the prize was awarded to James Peebles of Princeton University for his work in dark matter and dark energy).

Since then, over 4,000 other exoplanets have been found in the Milky Way, but apparently, none of them can be feasibly reached.

Stephen Kane, a professor of planetary astrophysics at the University of California in Riverside, agrees with Mayor. "The sad reality is that, at this point in human history, all stars are effectively at a distance of infinity," Kane told Live Science. "We struggle very hard as a species to reach the Earth's moon."

We might be able to send people to Mars in the next 50 years, but "I would be very surprised if humanity made it to the orbit of Jupiter within the next few centuries," he said. Since the distance to the nearest star outside of our solar system is about 70,000 times greater than the distance to Jupiter, "all stars are effectively out of reach."

Well, you might say, plenty of things seemed out of reach until we reached them, such as sending aircraft on intercontinental flights. But "in this case, the required physics to reach the stars, if it exists, is not known to us and it would require a fundamental change in our understanding of the relationship between mass, acceleration and energy."

"So that's where we stand, firmly on the Earth, and unlikely to change for a very, very long time," he said.

Mayor told the AFP: "We must take care of our planet, it is very beautiful and still absolutely livable."

Andrew Fraknoi, emeritus chair of the astronomy department at Foothill College in California agreed that we won't be able to travel to these stars in the near future. But "I would never say we can never reach the stars and possible habitable planets," he said. "Who knows how our technology will evolve after another million years of evolution."

Originally published on Live Science.

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Humans Will Never Live on Another Planet, Nobel Laureate Says. Here's Why. - Livescience.com

Dark matter, the mysterious substance making up a quarter of the mass and energy of the universe, might be made from extremely tiny and light particles, new research suggests. This fuzzy form of dark mattercalled that because these miniscule particles' wavelengths would be smeared out over a colossally huge areawould have altered the course of cosmic history and created long and wispy filaments instead of clumpy galaxies in the early universe, according to simulations.

The findings have observational consequences upcoming telescopes will be able to peer back to this early time period and potentially distinguish between different types of dark matter, allowing physicists to better understand its properties.

Related: 11 Unanswered Questions About Dark Matter

Dark matter is an unknown massive substance found throughout the cosmos. It gives off no light hence the name dark matter but its gravitational effects help bind together galactic clusters and cause stars at the edges of galaxies to spin faster than they otherwise would. Many scientists believe that most dark matter is cold, meaning it moves relatively slowly. But there are entirely different ideas, such as the possibility that it's tiny and fuzzy, meaning it would move quickly because its so light.

"Our simulations show that the first galaxies and stars that form look very different in a universe with fuzzy dark matter than a universe that has cold dark matter," Lachlan Lancaster, an astrophysics graduate student at Princeton University and co-author of a new paper in the journal Physical Review Letters, told Live Science.

Lancaster explained that the most common speculations about dark matter suggest it is composed of weakly interactive massive particles (WIMPs), which would have a few tens or hundreds of times the mass of a proton. Simulations that use this type of dark matter are extremely good at re-creating the large-scale structure of the universe, including vast voids of empty space surrounded by long, spidery filaments of gas and dust, a formation known as the cosmic web. But on smaller scales, such models contain a number of discrepancies from what astronomers observe with their telescopes. In this standard view, dark matter should pile up in the centers of galaxies, but nobody has seen it doing so.

Fuzzy dark matter, in contrast, would be mind-bogglingly light, perhaps a billionth of a billionth of a billionth the mass of an electron, according to a statement from MIT. Quantum mechanics states that particles can also be thought of as waves, with wavelengths inversely proportional to their mass, Lancaster said. So the wavelength of such a light particle would be thousands of light-years long.

Fuzzy dark matter would therefore have a harder time clumping together than cold, WIMP dark matter. In simulations, Lancaster and his co-authors showed that a cold dark-matter universe would have galaxies that formed relatively quickly out of spherical halos.

But fuzzy dark matter would instead coalesce into long, wispy strings of material "more giant filaments than clumpy galaxies," Lancaster said and galaxies would then be born larger and later. Dark matter would also have a harder time piling up in the centers of galaxies, potentially explaining why astronomers don't observe this clumpiness when they look at galaxies.

Instruments like the Large Synoptic Survey Telescope (LSST) in Chile and 30-meter-class telescopes being built around the world will soon be able to peer back to some of the universe's earliest days. They are expected to start taking data in the next decade, which means "we'll either start seeing the effects of fuzzy dark matter, or start ruling them out," Lancaster said.

Though other researchers have speculated about fuzzy dark matter, the new simulations do a more careful job of working out its cosmological effects, said Jeremiah Ostriker, an astrophysicist at Columbia University who was not involved in the work.

"This helps outline the details of what the formation of structure would be in this variant theory," OStriker added. "And it's one of the most interesting variant theories around."

Lancaster said his team's future simulations might focus on capturing more details of the fuzzy dark matter's effects, potentially giving astronomers a better idea of what they might expect to see through their telescopes.

Originally published on Live Science.

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Exotic 'Fuzzy' Dark Matter May Have Created Giant Filaments Across the Early Universe - Livescience.com

Astrophysics is not typically considered to be part of the humanities. Yet one class I took as a senior at university suggested otherwise. It left me in awe of the human mind.

With my own background rooted in the humanities, I found myself focusing on the way my professors described the cosmos. While the fantastical environments of black holes, white dwarfs and dark matter often took center stage, at the heart of each discovery was the human mind seeking to understand the unfamiliar.

Their tales of discovery made it clear that we often take our knowledge of the universe for granted. After all, the universe was not built for the human mind to understand. When we look up at the night sky, we see only a tiny fraction of what is out there. It is the task of the astrophysicist to develop a picture of the universe despite our overwhelming blindness.

I wanted to better understand how being human shapes our understanding of the universe. After talking to some of Princetons leading astrophysicists, one thing became clear: the discipline requires the human mind to be conscious not only of the universe but of itself (unless otherwise identified, all quotes are from these scientists).

Only 5 percent of the universe is normal, observable matter. Within this small fraction, the human eye can only perceive matter that emits light within a certain frequency on the electromagnetic spectrum. While birds can perceive magnetic fields and snakes can image in the infrared, we can detect only visible light. This range determines our picture of space, Adam Burrows explains. Our picture of space is, in that sense, a direct product of the human mind.

Rather than assume our picture wholly captured the universe, Jo Dunkley says that astrophysicists started wondering whether there might be other things filling our galaxies and universe that we cannot see. They designed telescopes to detect frequencies of light that lie beyond human perception, such as those of x-rays and radio waves. With these instruments, our picture of the universe became 5 percent complete.

The astrophysicists task then became one of using the visible to detect the remaining 95 percent. Einsteins laws of gravity provided a means of navigating the obscure. Because gravity depends solely upon mass, its effects can be seen irrespective of light production. As Dunkley explains, a massive, invisible object, such as a black hole, will attract a visible object, like a star.

While the Event Horizon Telescopes image of a black hole is one recent example, the strategy dates back as early as 1933. It was Swiss astronomer Fritz Zwicky who unwittingly first employed the technique when examining the behavior of galaxy clusters. He found the clusters to be far more massive than anticipated based on what was visible. He called the missing mass dark matter. Nearly 40 years later, American astronomer Vera Rubin confirmed its existence. While measuring the radial velocity of galaxies, she observed velocities incompatible with those predicted by the laws of gravity. The expectation had been that objects farther from the center of the galaxy orbited more slowly than those near the center. Rubin instead observed a constant velocity, meaning that there was no decrease at the fringe of the galaxies. In order for this to be possible within the laws of physics, there must be more to space than meets the eye, Dunkley explains. The mass existed, it just had yet to be detected.

Neta Bahcall explains that its the laws of gravity that render this dark matter indirectly observable. They allow astrophysicists to determine how much of the universe is invisible without knowing exactly what the darkness is. James Jeans once likened the situation to Platos well-known allegory, where imprisoned in our cave, with our backs to the light, we can only watch the shadows on the wall. The comparison is apt. Counterintuitively, the shadows here represent what is visible, and the light represents what we cannot see or even imagine. With this technique, dark matter came to contribute 27 percent to our cave drawing of the universe.

The 68 percent of the universe absent from our drawing is still unknown. But, in 1998, that unknown was given a name: dark energy. It emerged as a means of explaining the universes anomalous expansion. In the 1990s, astrophysicists thought that the universes rate of expansion would gradually decrease. The laws of gravity predicted that the matter filling the universe would begin to pull itself together as time went on, thus slowing the universes expansion. Yet this turned out not to be the case. The expansion was accelerating. Very little is known about dark energy, and so our picture of the universe remains far from complete.

The problems facing our picture of the universe are not limited to what we can perceive. As Ed Turner explains, our mind and the culture in which it was formed condition the way we explore the universe. Because of this particular conditioning, we have mental blind spots for the cosmic phenomena that run counter to human intuition and understanding. For instance, Turner claims that the mind is predisposed to see things as statistically significant when they might not be. We erroneously perceive patterns in the spacing of stars and of the planets in the solar system, seeing them as though they were arranged.

There are other properties of the mind that get in the way of seeing the truth, according to Turner. Consider, for instance, our belief that massive objects must take up space. It is not a direct relationship: we accept that a piece of lead is more massive than a pillow, even though the latter is larger. At the extremes, however, we expect some positive correlation between the two. The extreme physical environment of a neutron star then poses problems. As Michael Strauss suggests, the star is so dense that a thimbleful of neutron star material has the mass of 70 million elephants. We cannot help but wonder: where is all the mass?

We are blinded by being human when we look at something larger than the human experience, Robert Lupton explains. It becomes further apparent when we are confronted with counterintuitive phenomena like white dwarfs and black holes. White dwarfs decrease in size as they become more massive, says Joshua Winn, and for black holes, all mass is compressed to zero size. While we cannot see the black hole, giving the phenomena a name allows us to imagine it. The same could be said of dark matter and dark energy, explains Dunkley. As with the previous analogy, language provides a means of overcoming our initial blindness to interact with these cosmic phenomena.

Astrophysicists encounter another blinding property of the mind when considering the nature of space: we can only visualize in three dimensions. In order to imagine the geometry of space namely whether it is flat or curvedwe would need to be able to think in four dimensions, says Dunkley. For instance, to determine the curvature of a ball, we first picture the ball in three dimensions. Therefore, to determine a three-dimensional curve, the mind would need to picture the four-dimensional object.

This need arises when astrophysicists contemplate the expanding universe and relativity. For the former, the task is to conceptualize a three-dimensional universe that exists in a loopan impossible visualization, for connecting every dimension would create a four-dimensional object. For the latter, in order to explore the relativistic behavior of spacetime, the task is to imagine a three-dimensional space deformed by gravityanother impossibility.

In both cases, two-dimensional analogies facilitate understanding. Dunkley likens the universe to a piece of string attached at both ends to create a loop, and then relies upon language to bridge the-dimensional gap. We would connect every side of space, such that no matter the direction we traveled in, we would always return to our starting point, she explains. Similarly, in his 1915 paper on general relativity, Einstein used a trampoline as a two-dimensional analogue for space. He then turned to language to illustrate how placing a massive object upon the stretchy surface creates a third, vertical dimension. The same principle applied in more dimensions, he argued: massive objects bend space. While we are still unable to visualize the four-dimensional phenomena, Dunkley says that through these linguistic analogies, we can imagine the consequences.

In this manner, astrophysicists stretch the mind to see the universe from an external perspective, says Turner. Burrows speaks of retraining the brain by developing a new language better suited for the conversation between the cosmos and the individual. The environment of the universe is so different from our daily environment that often we cannot imagine it, according to Joel Hartman. Take, for instance, the size of the universe and the number of stars within it. The language of mathematics, grounded in scientific notation, logarithms and orders of magnitude, allows us to grapple with the cosmos where words fall short, explains Burrows.

Similarly, when considering the four-dimensional universe, mathematical measurements provide astrophysicists with an invaluable means of navigating the obscure. Just like in two dimensions, explains Dunkley, if the geometry of space is flat, then parallel lines, like light rays, stay parallel always. If the space is curved, then they will either come towards each other in a positively curved universe or splay apart in a negatively curved one. To return to the language of Platos cave, it seems that by measuring the shadows before us, we are able to conceptualize, in part, the nature of what remains out of sight and out of mind.

Even with this universal language of mathematics, astrophysicists still resort to biological terms to describe certain cosmic phenomena. Turner describes how astrophysicists speak of the birth and death of stars, as though they were alive. More extreme is the twin paradox devised to facilitate a correct conception of time. We are accustomed to thinking of time as strictly linear and independent, but Einsteins theory of relativity says that probably is not the case. Time passes more slowly when close to massive objects.

To overcome our intuition, astrophysicists imagine taking two twins and somehow sending one of them to spend time near a black hole, [so that] she would actually age more slowly than [her] Earth-dwelling partner, explains Dunkley. The physical manifestation of aging allows the mind to grapple with the nonuniformity of time, for we are able to envision two differently aged twins despite the semblance of a paradox.

While there are certainly properties of the mind that get in the way of seeing the truth, as Turner says, the fact that it is human allows us to engage with the universe. The lives of stars and the twin paradox are just two examples of astrophysicists making sense of the unfamiliar through our own biology. After all, it is the mind of the astrophysicist that must first identify its blind spots and then devise techniques to overcome them. In that sense, astrophysics and humanism go together in a wonderfully unexpected way. As the literary critic Leo Spitzer once wrote, the humanist believes in the power of the human mind of investigating the human mind.

So often the predominant reaction to astrophysics focuses on how vast the universe is and how insignificant a place we hold in it. It would be far better to flip the narrative to see the marvel of the mind exploring the cosmos, human lens and all.

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How Mere Humans Manage to Comprehend the Vastness of the Universe - Scientific American

Mired in a growing frustration with how political polls were being reported on, a Quebec astrophysicist tried his hand at aggregating polls and projecting the 2018 Quebec election. Three provincial elections later, Philippe Fournier is hoping to correctly predict 90 per cent of the winning candidates of the Oct. 21 vote.

From coast-to-coast-to-coastfrom Nunavut to Skeena-Bulkley Valley, B.C., to Avalon, N.L.338Canada dives into individual races, as the websites name suggest, across all of Canadas 338 ridings.

I was looking at some Quebec polling before the [2018] election, and I noticed that many articles in newspapers were just badly written. Some journalists are told to write about polls when they dont know much about polls and statistics, Prof. Fournier told The Hill Times in a phone interview, a little more than a week before the Oct. 21 election.

I told my students I could do much better than that, he said.

Prof. Fournier teaches astrophysics at Cgep de Saint-Laurent in Montreal, where he is currently teaching only part timeas he currently spends 70 to 80 hours per week on 338Canada.

He first became involved in polling aggregation in the Quebec provincial election in 2018, when he started writing about polling projections on his website qc125.com.

It took about three months and then La Presse in Montreal contacted me asking me questions and political parties contacted me asking me questions. So it kind of became viral, Prof. Fournier said. It went so well that after the Quebec election, I figured, well, why not do a Canada-wide system.

The distinctive feature, Paul Adams, a journalism professor at Carleton University and former EKOS pollster, said of 338Canada, is the individual riding projections.

To get insight on the individual ridings, an aggregator takes the regional and subregional polling results, and apply them to historical patterns, Prof. Adams said.

As of Oct. 15, 338Canada is projecting a close race between the Conservatives and Liberals. The Hill Times photograph by Andrew Meade

Where aggregators can miss in its projections is where there is no historical baseline.

In this election, the obvious one would be Maxime Berniers party [the Peoples Party], Prof. Adams said. We dont actually know where we would expect them to run stronger.

How the Peoples Partys 2.8 per cent national support, according to 338Canada, will be distributed in certain individual ridings remains an unknown, Prof. Adams said.

So far, Prof. Fournier has worked on three provincial elections where he correctly projected more than 90 per cent of the winning candidates over the three votes. In the 2018 Ontario election, which resulted in a Progressive Conservative government, he identified 111 of the 124 winning candidates; 11 of the 13 misses were within the margin of error. In the 2018 Quebec election, he identified 112 of 125 correct candidates; of the 13 misses, four of them were in the margin of error. His most recent projections during the 2019 Alberta provincial election were his most successful, identifying 94 per cent of the successful candidates. He projected 82 of the 87 winning politicians. Of the five that he missed, three were within the margin of error.

I dont aim for perfection because its statistics and I know its impossible, Prof. Fournier said about projecting the Oct. 21 federal vote. I have this threshold that I want to reach: 90 per cent. But 90 per cent means I will miss about 35 [ridings].

The election right now is so close that I might miss more. So it might be 85 per cent. But my desire would be 90 per cent. Above that is unrealistic, he said.

As of Oct. 14, 338Canada was projecting the Conservatives to win 135.8 seats, and the Liberals to take 134.9 seats, both with massive margins of error. As he explained in Macleans, Prof. Fournier said his model has no fewer than 139 of 338 electoral districts labeled as either toss up or leaningmeaning more than a third of all ridings remain too close to call. A week before the election, the Bloc was projected to win 32.4 seats, the NDP 30.1 seats, the Green Party at 3.8 seats, and Independents and the Peoples Party at less than one seat apiece.

Prof. Fourniers model takes into account demographics of ridings, as well as historical performance and the effect of star candidates.

Pollster Greg Lyle, president of Innovative Research, said in cases where there is a strong candidate challenging an incumbent its hard to quantify what will tip the scales.

Mr. Lyle pointed to the current campaign in Kamloops-Thompson-Cariboo, B.C., which has been held by Conservative MP Cathy McLeod since 2006. But her current Liberal challenger is Terry Lake, a former Kamloops mayor and B.C. health minister.

A lot of Conservatives have been used to voting for Terry Lake, because provincially they vote B.C. Liberal, he said. And Terry Lake was very well regarded, so he has a strong personal brand.

In that seat, would you put your finger on the scale for the Liberals if it was close, Mr. Lyle said. But once you do that, now you are not betting on the methodology anymore, youre betting on the grey area.

As of Oct. 15, 338Canada is projecting that Ms. McLeod is likely will win re-election, with Mr. Lake finishing a distant second place.

Prof. Fournier said initially some pollsters werent all receptive to his modelling.

There are amateurs online and Im sure those amateurs really grind the gears of many pollsters. I know some pollsters really dont like aggregators, he said.

When he first started Qc125.com, Prof. Fournier said pollster Jean-Marc Lger was initially not pleased with him.

[Mr. Lger said,] I didnt know you were a scientist, I thought you were just some guy on the internet pulling numbers. Like everything on the internet, there are amateurs that just do anything and there are the serious people, Prof. Fournier said.

In addition to the website, Prof. Fournier also writes about his polling aggregate projections for Lactualit and Macleans.

When looking at historical examples, Prof. Fournier takes into account the 2011 and 2015 elections.

I look further in the past for some districts, he said, but the thing is the demographics in some parts of the country, especially the urban areas changed so fast [that] they would not be very useful to use the 2004 [or] 2006 numbers.

Prof. Adams said, generally speaking, aggregators are better than individual pollsters in predicting outcomes.

Pollster Frank Graves, pictured at the Green Partys 2016 convention in Ottawa, says aggregators can have the corrosive impact on a voters decision to not cast a ballot. The Hill Times photograph by Sam Garcia

Thats not to say that in any given election, there may be an individual pollster that comes out better than the aggregations, but the problem is you cant predict in advance which pollsters that is going to be, he said. Youre safer to stick with the aggregators.

There are two key concerns that aggregation has to focus on to influence the success of the model, Prof. Adams said. Aggregators have to decide the way each individual will be weighted and when to discard old polls for the aggregation model.

For Prof. Fournier, he will weigh a poll down in his model if the results are too out of line with the overall average. But, he said, if subsequent polling shows that the poll wasnt an outlier and was a precursor, it will regain its weight.

Outside of campaigns, Prof. Fournier said he can keep a poll in the model for around two months given how slowly the numbers move. As the poll gets older, the less weight it will have in the model.

During the election, Prof. Fournier said, he will only keep a poll in the model for a week.

Prof. Adams said if a poll is kept in the model for too long, it can miss the rapidly changing mood of an electorate.

If you take a weeks worth of results, you have a larger total number of cases, like you have tens of thousands of cases potentially adding up all the different polls, in a more stable environment that would give you a better result than just one or two polls at the end of the campaign. But if theres movement at the end of the campaign then a failure to decay older polls quickly enough will not serve you as well, he said.

EKOS Research president Frank Graves said he didnt think the aggregators are adding a service that cant be done elsewhere, as many pollsters put out their own seat projections.

Over the years, Mr. Graves said EKOS has performed better than the aggregators in projecting seats. In the 2006 federal election, EKOS projected the Conservatives would win 125 seats, plus or minus five seats. In the end, the party won 124 seats.

Mr. Graves said a seat projection should be within 20 seats of the winning party.

He added that if the aggregators are inaccurate or overstating their precision, there can be a corrosive impact on the voter decision making, as some people may decide not to vote if they look at a projection and see one candidate projected to win easily.

I would not rule out the fact that the aggregators contributions in the U.S. presidential election couldve been the victory for Donald Trump because a lot of disaffected, weakly-engaged Hilary [Clinton] voters were told, This is mailed in. Its done. Dont worry. And they stayed home [on election day], Mr. Graves said.

nmoss@hilltimes.com

The Hill Times

Neil Moss is a reporter at The Hill Times covering federal politics, foreign policy, and defence.- nmoss@hilltimes.com

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The astrophysicist whose polling aggregator is projecting the election - The Hill Times

PUBLISHED: 16:03 15 October 2019

Rebecca MacNaughton

Immerse yourself at Norwich Arts Centre on Tuesday October 22 and Wednesday October 23. Picture: [UNIT]

Archant

Have you ever wondered what a star looks like when it is born, how you measure the speed of light or why dogs are so important to spaceflight? Head to Norwich Science Festival, October 8-26, to get the answers.

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Ever since man walked on the moon 50 years ago, we've been fascinated by space. It has populated our favourite books, films and TV shows for decades and now, with the advent of commercial space tourism, more of us might get the chance to explore it.

Head to The Forum on Friday, October 25 to find out how spaceflight has changed over the years as journalist and broadcaster, Richard Hollingham, returns to his hometown to chair a panel called The Future of Human Spaceflight: The Moon, Mars and Beyond.

He will be joined by a diverse panel of experts, including space engineering consultant and founder of Rocket Women Vinita Marwaha Madil, journalist and broadcaster Sue Nelson, medical doctor and ESA researcher Beth Healey and University of Southampton researcher Christopher Ogunlesi. Together, they will discuss how spaceflight has changed since the Apollo missions and how commercial space tourism is set to bring a wider cross-section of people to orbit - and, he says, the panel will also share some important insights on how women have shaped the course of the 21st century space race.

Richard will also return to The Forum on Saturday, October 26 for Space Dogs, an exploration of how canine cosmonauts have paved the way for human exploration. "Dogs are the great unsung heroes of space," says Richard. "Every astronaut from Yuri Gagarin to Tim Peake owes their experiences to these pioneering space dogs."

He'll detail how stray dogs from the Soviet Union paved the way for human spaceflight and look at some of the key canine cosmonauts, from Laika - the first dog sent to space in 1951 - to Belka and Strelka who, Richard says, "flew, orbited and returned to Earth to be hailed as Soviet celebrities."

If you've ever wondered how science and art can work together, then head to Norwich Puppet Theatre on Friday, October 25 from 7-8.35pm, as The Cosmic Shambles Network presents Signals, a comedy play that follows two astronomers as they hunt for alien life.

The show asks some pretty hefty questions about the search for meaning - "what if we did find aliens?" asks producer Trent Burton, "how would humanity react, how would those two individuals react?" - as well as the role of art in science.

"The Cosmic Shambles Network blurs the line between science and art - once people get over the initial idea of it, they realise it's a much more natural fit than they thought," says Trent.

The performance will also be followed by a talk from Stargazing Live's Professor Lucie Green as she unpicks some of the science behind the show. "There's some really nice science in the show so the talk afterwards will expand on that," says Trent. "It's a great juxtaposition between these two people, stuck at a desk, and what these questions, at the edge of the universe, could mean."

There will also be a night of music at The Octagon Chapel on Saturday, October 26 as The Sky at Night's Prof Chris Lintott presents The Crowd and the Cosmos before being joined by acclaimed musician Steve Pretty - expect a unique, out of this world evening as they perform a special version of their acclaimed show, Universe of Music.

DON'T MISS OUT

October 22-23

[UNIT]: [REACH THE MOON]

Norwich Arts Centre, 2-2.45pm, 6-6.45pm and 8-8.45pm

Cost: 4/6/9/12

Age: 5+

Immerse yourself in these audio/visual performances which celebrate the 50th anniversary of the first moon landing. It will be an all-encompassing audio/visual feast which innovatively marries science with art.

October 26

Radio Blips and Blasts: Pulsars and our Understanding of the Cosmos

The Forum, Millenium Plain, 3.30-4.30pm

Cost: Free

Age: 12+

Since their discovery in 1967, observations of pulsars - the incredibly dense, highly magnetic, rapidly rotating remnants of supernova explosions - have been used to increase our understanding of fundamental physics. In this talk, UEA's Dr Robert Ferdman will discuss the state of astrophysics leading up to, and including, this momentous discovery.

Introduction to the Universe: Sleep Not Essential!

The Forum, Millenium Plain, 5-6pm

Cost: 5

Age: 12+

TV astronomer and author Mark Thompson will expound the wonders of the Universe in a warm-up up to his 2020 record-breaking attempt to lecture for five days straight with no sleep! Anything could happen.

Buy tickets and find out more at http://www.norwichsciencefestival.co.uk

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Norwich Science Festival launches with physics and astronomy events | What's on and things to do in Norfolk - Eastern Daily Press

The ConversationOct 14, 2019 16:04:31 IST

During the press conference in which he was revealed as one of the winners of the 2019 Nobel Prize in Physics, James (Jim) Peebles was asked to point to a single discovery or breakthrough from his long career that would put the award in context. Peebles demurred, replying instead: Its a lifes work.

Thats a perfect description of his contribution to our understanding of the universe. His is a career so influential that he is widely recognised as one of the key architects of the field of physical cosmology, the study of the universes origin, structure and evolution. I am sure I am not alone in regarding Peebles as the greatest living cosmologist.

Nobel Physics Prize winner- James (Jim) Peebles. image credit: Princeton University/EPA

Peebless research career started in the early 1960s. The Canadian-born scientist earned his undergrad at the University of Manitoba and later gained his PhD in the group of Robert Dicke at Princeton University in New Jersey in 1962. He has remained there ever since. Peebles now holds the title of Albert Einstein Professor of Science at Princeton.

In the 1960s, Dickes group was working on theoretical predictions and the corresponding observational consequences for the state of the primordial universe, the phase immediately following the Big Bang lasting for a few hundred thousand years. At that time the Big Bang theory for the formation of the universe was not yet fully accepted, despite observational evidence that galaxies were moving away from each other.

Dickes group was working on the theory that if the universe was expanding, then it must have been much smaller, hotter and denser in the past. The prediction was that the thermal radiation from this epoch might be still be observable today as background radiation pervading the universe. The Princeton group was also designing instruments to try to detect it.

Meanwhile, Arno Penzias and Robert Wilson, working for Bell Labs (also in New Jersey), had detected an unusual persistent background noise in their experiment. They were investigating the use of high altitude echo balloons, a kind of early satellite communication.

When Penzias and Wilson approached Dickes group for advice, it became clear that they had actually detected the relic background radiation. We call it the cosmic microwave background (CMB) because the radiation peaks in the microwave part of the electromagnetic spectrum.

A map of the universes cosmic microwave background radiation. image credit: NASA

The resulting papers were arguably the birth of the field of observational cosmology, a branch of physics that has revolutionised our view of the cosmos and our place within it. Peebles played a pivotal role in our theoretical understanding of the primordial universe and its evolution, but he also recognised that the CMB was a treasure trove of information that could be plundered. In particular, it holds clues about the formation of cosmic structures the galaxies and indeed clues about the fundamental nature of the universe itself.

Much of Peebless work has focused on understanding the emergence and growth of structure in the universe from the relatively smooth primordial conditions encoded in the CMB. In the process he has helped define an entire field of study.

For example, in the early 1970s, he was one of the first to run computer simulations of cosmic structure formation, a practice that is an entire branch of research today, where cosmologists explore toy universes.

Peebles helped usher in the dark sector to our model of the universe, becoming a pioneer of (what is now called) the standard cosmological model. In this model, the universe is dominated by mysterious forms of matter and energy that we are yet to fully understand, but whose existence is supported by observational evidence. Normal matter now has an almost negligible cosmic relevance compared to this dark matter and dark energy.

Peebles has produced such an immense body of work it is impossible to do it all justice in this short article. In one of his most influential papers, he linked the subtle fluctuations in the temperature of the CMB which reflect ripples in the density of matter shortly after the Big Bang with the way in which matter is distributed on a large-scale throughout the present day universe. The link exists because all the structure we see around us today must have grown through the evolution of those primordial seeds.

Peebles advanced the concept of a dark matter component to the universe and its implications for the evolution of structure. Through this, and other work, he helped establish the theoretical framework for our picture of how galaxies have formed and evolved. And he demonstrated how observations of the CMB and the distribution of galaxies could be used as evidence to help measure key cosmological parameters, the numbers that feature in the equations we use to describe the nature of the universe.

The influence of Peebles doesnt end there. Aside from his monumental contributions to fundamental research, spanning the CMB, dark matter, dark energy, inflation, nucleosynthesis, structure formation and galaxy evolution, his textbooks have educated generations of cosmologists. They will do for years to come. His Principles of Physical Cosmology is on my desk right now.

In the Nobel press conference, Peebles was keen to highlight that he didnt work alone. But to say that he has been largely responsible for shaping our understanding of the universe is a cosmic understatement.

James Geach, Professor of Astrophysics and Royal Society University Research Fellow, University of Hertfordshire

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

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Nobel Prize in Physics: James Peebles, master of the universe, shares award - Firstpost

Two NASA astronauts are due to make history this week by taking part in the first ever all-female spacewalk.

Astronauts Christina Koch and Jessica Meir will work to fix the power system of the International Space Station (ISS), the habitable satellite which is in orbit 220 miles above the Earth's surface.

The momentous spacewalk was due to take place on October 21. But NASA announced on Tuesday it would be pushed forward to Thursday or Friday.

In a change to their brief, the pair will replace a faulty battery charge-discharge unit, which is currently preventing a new lithium-ion battery installed earlier this month from powering the ISS.

The ISS is fuelled by a collection of thousands of solar cells known as arrays. Battery charge-discharge units control how much charge batteries which collect energy from these arrays receive.

NASA officials explained during a press conference attended by Space.com that the issue stems from a battery pack which was swapped in April.

Despite the broken unit, NASA gave assurances in a statement that the crew is safe and their laboratory experiments onboard the ISS have not been disrupted.

The postponed spacewalk due to take place on 21 October would have been the fourth of 10 planned to take place between October and December, as part of what is known as Expedition 61.

Commanded by the European Space Agency's Luca Parmitano, the mission includes NASA astronauts Koch, Meir, and Andrew Morgan, as well as Russia's Aleksandr Skvortsov and Oleg Skripochka.

Meir and Koch had originally planned to help replace nickel-hydrogen batteries with "newer, more powerful" lithium-ion batteries on the far side of the ISS's port truss, according to NASA. The work is a continuation of an upgrade of the stations power system which started in January 2017.

The second half of the sequence, expected to start in November, will see crew members fix the space station's alpha magnetic spectrometer.

Meir joined Kochwho holds the record for the longest single spaceflight by a womanat the satellite in late September, and will spend over six months on the ISS.

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The first all-woman spacewalk was controversially postponed in March as there were not enough medium-sized space suits on the ISS to fit both women. NASA astronaut Anne McClain was scheduled to join Koch in updating the ISS's power sources. But McClain arrived back on Earth in June, completing a 204-day mission.

In March, McClain became the 13th woman to complete a spacewalk, followed by Koch a few days later.

McClain tweeted back in March: "This decision was based on my recommendation. Leaders must make tough calls, and I am fortunate to work with a team who trusts my judgement. We must never accept a risk that can instead be mitigated. Safety of the crew and execution of the mission come first."

Dr. Scott G. Gregory, lecturer in astrophysics at the University of Dundee, told Newsweek the all-female spacewalk is "both historic and inspirational."

"Despite many talented female scientists and engineers, spacewalks have been a male-dominated activity," he said.

"Although there have been female spacewalkers before, it has always been with a male counterpart. This first all-female spacewalk is long overdue. Jessica Meir and Christina Koch are following their childhood dreams of being astronauts and 'walking' in space. It represents years of dedication, study, hard work, and pushing limits and that is truly inspirational."

Gregory said he'll be watching the live stream of the spacewalk with his 5-year-old daughter.

"We'll be following the news as Jessica Meir and Christina Koch write their own history."

"All over the world lots of little girlsand little boyswill be watching and they'll be dreaming that they'll be walking in space when they're grown up," he added. "If that inspires them to dedicate their lives to scientific or technological endeavours, this can only be a positive for all of society."

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What the Women of the First All Female Spacewalk Will Do at the ISS - Newsweek

Brian OHalloran of Liberty IT discusses his work as a data scientist and the unusual route that led him to where he is now.

Brian OHalloran is a data scientist at Liberty IT, working on natural language programming projects and managing stakeholders. But before joining the company, he was a researcher in astrophysics and went on to work at the Daily Telegraph, among other roles.

Here, he tells Siliconrepublic.com about the world of data science, and the transferable skills that made his colourful career path possible.

Working as a data scientist is not too far removed from my academic roles. You get to do R&D, after all BRIAN OHALLORAN

Prior to joining Liberty IT, I was lead data scientist at the Daily Telegraph in London, working on things like recommendation systems for users and building election models for Westminster elections. Before that, I was in a similar role at eFinancialCareers again in London which I joined after leaving academia.

I used to be an astrophysicist. My area of interest was galaxy evolution, particularly focused on nearby dwarf galaxies as theyre excellent proxies for understanding how galaxies evolved in the early universe.

I spent four years as a postdoc in Washington DC, working on projects focused on this type of research, followed by another six in London. The latter role was as part of the European Space Agencys Herschel Space Telescope project, working on the SPIRE instrument team.

I graduated from NUI Maynooth with a BSc in experimental physics and mathematics in 1998, followed by a PhD in experimental physics from UCD in 2003.

Obviously, I picked up the hard skills for analysing, breaking down and solving problems during this time. What was invaluable though, in terms of my current role, were the soft skills that you pick up by accident and through stealth.

I spent quite a lot of time teaching physics and astronomy courses, and learned invaluable soft skills in terms of communication of ideas and people and stakeholder management, something particularly of value when dealing with C-suite and non-technical stakeholders!

Well, that depends on the problem, of course. Ive spent quite a lot of time working on natural language programming projects during my data science career. Most of my actual development time is spent knee-deep in Python, TensorFlow, Keras and Spacy.

At Liberty IT, weve migrated our DS frameworks to the cloud. Were increasingly using Amazon SageMaker and their competitor from Microsoft, and both loom large in our future.

Ive been lucky to have not just one, but a number of hugely influential people throughout both my academic and data science careers. My PhD supervisor at UCD, Brian McBreen, played a huge role in the development of my academic career.

In terms of my data science career, my bosses and colleagues at the Telegraph were greatly influential in where I am today, including Magda Piatkowska, Herv Schnegg and Dimitris Pertsinis.

In some ways, working as a data scientist is not too far removed from my academic roles. You get to do R&D, after all, and so are given a lot of leeway in that regard, which is great as it allows you to be very creative.

I really enjoy working with stakeholders, as it is very much a two-way street in terms of education and evangelising. If you do it right, you get to iron out what they are looking for as a final product, everyone gets excited and commits to the project. Stakeholder buy-in and proper communication back and forth are such crucial components of success in the data science field. Without either, projects are doomed to failure.

The data science function at Liberty IT is very new, so theres huge potential for projects across the Liberty Mutual Insurance Group, with us at the heart of that. Its a really exciting time and place to be in.

Data science functions that work well and that add real business value. If more and more firms crack that problem, its a really exciting trend. The rest, in terms of trends, is really just window dressing.

Brush up on those soft skills. Learn to network, learn how to listen to your stakeholders. Theres no point in building technically wonderful solutions if theres no customer willing to use them.

Data scientists need to stay away from ivory towers at all costs. Make sure you do too.

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Can you pivot from studying galaxy evolution to working in data science? - Siliconrepublic.com

AMC's "The Walking Dead" launched its 10th season last week to the delight of zombie fans everywhere, but the premiere also contained a space junk Easter egg that just might be a major plot point for the series: a Soviet satellite crashing to Earth.

The episode "Lines We Cross" ends with an old Soviet satellite crashing to Earth as a brilliant daytime fireball. It loses unmistakable sonic booms and a sparks wildfire in enemy territory (watch out for Whisperers!) that the show's heroes must battle to save their hunting grounds.

"We'd been talking the the writers' room about what are different things that happen the more time goes on," executive producer Angela Kang said in AMC's "Talking Dead" recap of the Oct. 6 premiere. "We thought that it would just be like an interesting thing that we haven't dealt with before, and then see what things they can get from the satellite in terms of technology or to help them."

Related: The Biggest Spacecraft to Fall Uncontrolled from SpaceMore: Failed 1970s Venus Probe Could Crash to Earth This Year

A Soviet satellite falls to Earth in a brilliant fireball in AMC's "The Walking Dead" Season 10 premiere "Lines We Cross,"

(Image credit: AMC)

According to Kang, "The Walking Dead" showrunners sought advice on satellites from a NASA scientists at the Jet Propulsion Laboratory in Pasadena, California.

That got us wondering how accurate the satellite crash depiction was, so we reached out to astrophysicist Jonathan McDowell at the HarvardSmithsonian Center for Astrophysics in Cambridge, Mass. who tracks satellites and space junk in Earth orbit.

Our first question: How accurate is the fireball, sonic boom and crash, which leaves much of the satellite intact?

"The visual of the reentry ... is good, although it looks too high at that point to have audible sonic booms, I would guess. Overall, not bad as a depiction," McDowell told Space.com in an email. "The almost-intact satellite found on the ground ... is not plausible."

The appearance of "The Walking Dead" satellite resembles a type of old Soviet surveillance satellite known as a Tselina-R, which was used for electronic intelligence, McDowell said.That might just be a coincidence, though.

According to Russian spaceflight expert Anatoly Zak, who runs Russianspaceweb.com, Tselina-R launched in 1990 (before the end of the Soviet Union) and was designed to last about six months. But Tselina-class satellites were launched throughout the late 1960s, 70s, 80s and 90s, with the last to fly in the early 2000s.

Next question: Is 10 years in "The Walking Dead" (that's my estimate based on the show's seasons) enough time for satellites to fall from space?

"The 10 years is enough if the satellite were in a relatively low orbit of say 500 km," McDowell said. "It'd be unlikely to have a jet-engine-size bit surviving unless it was actually designed for reentry (like a camera/film capsule)."

Some Soviet satellites like that depicted in "The Walking Dead" have had small engine parts, like a meter-sized plate or quarter-meter spherical pressure tank, survive, but nothing the size of what appears in the show, McDowell added.

"Maybe you'd get a piece that big from a space station module."

Related: Skylab's Remains: NASA Space Station Debris in Australia (Photos)

The remains of a Soviet satellite in AMC's The Walking Dead. Such a large piece of space junk from a satellite would be unlikely in reality, unless it was designed to survive reentry.

(Image credit: AMC)

Here's a follow-up: The folks in "The Walking Dead" rush to the Soviet satellite to put out a wildfire, then rush to salvage any technology they can. Wouldn't there be toxic hydrazine or other chemicals to worry about? And would anything be salvageable at all?

"It's unlikely there'd be anything usable surviving I don't think anything from Skylab survived in repairable condition for example," McDowell said. "Again, if [it were] part of a system designed for reentry, that's a different story, so you could imagine a cargo ship ([SpaceX's] Dragon, for example) that boosted its recovery module in the wrong direction and was stranded in orbit for reentry 10 years later but it wouldn't look like that."

And McDowell suggests there might be more to worry about than just toxic hydrazine, a fuel used for spacecraft thrusters.

"Theconcern with hydrazine is valid but maybe brief it would probably dissipate pretty quickly. I would certainly be hesitant about approachingthething when not wearing a protective hazmat suit," McDowell said. "There might be potentially explosive hypergolic propellant on board too. And on an old Soviet sat there might be high-explosive self destruct devices."

Okay, last question: Do you watch "The Walking Dead"?

"I'm not a big zombie fan, 'Walking Dead' is too gross for me," said McDowell, though he did enjoy the TV series "iZombie."

McDowell also enjoy another show about the dead walking the Earth, HBO's "Dead Like Me," which began with Russia's Mir space station falling to Earth and its toilet seat killing the show's lead character.

"I was a fan of 'Dead Like Me,' indeed," McDowell said, "and appreciated the (again, implausible) Mir toilet seat."

Episode 2 of "The Walking Dead" Season 10 airs tonight on AMC at 9 p.m. EDT/8 p.m. CDT.

Email Tariq Malik attmalik@space.comor follow him@tariqjmalik. Follow us@SpacedotcomandFacebook.

Need more space? You can get 5 issues of our partner "All About Space" Magazine for $5 for the latest amazing news from the final frontier!

(Image credit: All About Space magazine)

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A Soviet Satellite Falls to Earth in 'The Walking Dead' Season 10. How Realistic Is It? - Space.com

Typically, even the full Moon is approximately 400,000 times less bright than the Sun is, making it appear about 12-14 visual magnitudes dimmer to human eyes. While, in visible light, the Sun always outshines the Moon (due to the latter reflecting the former's light), there is one part of the spectrum where the Moon can even outshine the Sun after all.

To human eyes, the Moon is the second brightest visible object, trailing only the Sun.

As seen in X-rays against the cosmic background, the Moon's illuminated (bright) and non-illuminated portions (dark) are clearly visible in this early X-ray image taken by ROSAT. The X-rays, like almost all wavelengths of light, arise mostly from reflected emission from the Sun.

Moonlight is just reflectedlight generated from other sources;it's not self-luminous.

The size, wavelength and temperature/energy scales that correspond to various parts of the electromagnetic spectrum. You have to go to higher energies, and shorter wavelengths, to probe the smallest scales. Although the Moon reflects sunlight, the most energetic photons from the Sun normally top out at X-ray energies.

Across the whole electromagnetic spectrum, the Sun always appears much brighter than the Moon.

This 1991 photo shows the Compton Gamma-Ray Observatory being deployed in space during April 7, 1991 from the Space Shuttle Atlantis. This observatory was humanity's first space-based gamma-ray satellite, and was part of NASA's original great observatories program which included Hubble, Compton, Chandra and Spitzer.

Until, that is, we launched the Compton gamma-ray observatory, capable ofmeasuring the highest-energy radiation.

A diagram of the EGRET instrument, which was used for observing the highest-energy photons aboard the Compton Gamma-Ray Observatory. The EGRET instrument is the only one capable of measuring photons with energies between about 20 MeV up to around 30 GeV: higher energy photons than the Sun typically emits.

The Sun, in gamma-rays, is very quiet, as its emitted radiation tops out at X-ray energies.

The Sun's light across the electromagnetic spectrum is due to nuclear fusion, which primarily converts hydrogen into helium. The nuclear reactions produce neutrinos and radiation that extends from the radio all the way up into the X-ray, but gamma-rays are only produced rarely: during flaring events.

The Moon, on the other hand, emits very little light relative to the Sun, but outshines it in gamma-rays.

Between 1991 and 1994, the Moon passed into the Compton Gamma-Ray Observatory's field-of-view multiple times, where the instrument was capable of observing it. Compton detected high-energy gamma-rays from the Moon with its EGRET instrument, and the energy spectrum of the lunar gamma radiation are consistent with a model of gamma ray production by cosmic ray interactions with the lunar surface. The Moon is brighter than the (non-flaring) Sun in these high energies.

Across the full electromagnetic spectrum, only in the highest-energy gamma-rays does the Moon outshine the Sun.

A thin crescent moon, just one day after the new moon, sets in the west. The remaining disk is still illuminated by the light reflected from Earth that's then incident upon the lunar surface. The fact that the Moon always appears full in Gamma-Rays,even when just a thin crescent is illuminated by the Sun, teaches us that it isn't reflected sunlight that's causing these lunar Gamma-Rays.

This observation aloneteaches us that the Moon isn't generating its gamma-rays by reflecting sunlight.

Using data from NASA's Lunar Reconnaissance Orbiter (LRO) and its narrow angle camera (LROC), we can now construct 3D models of the surface of the Moon and simulate any potential landing sites for missions. Our current understanding teaches us that the Moon's surface is made of many heavier elements, is surrounded by practically no atmosphere at all, and has a negligible magnetic field. This combination of factors basically creates 'the perfect storm' for generating gamma-rays from high-energy nuclear recoils.

Unlike the Sun,the Moon's surface is made of mostly heavier elements, while the Sun is mostly hydrogen and helium.

The only time the Sun produces gamma-rays is during flaring events, when accelerated, high-energy protons can collide with heavier nuclei, producing an excited-state nucleus that emits gamma-rays. During quiet conditions, these fast protons will only interact with hydrogen or helium nuclei, which do not produce these gamma-rays. On the Moon's surface, however, heavy nuclei abound, and the creation of excited-state nuclei that then emit gamma-rays is ubiquitous.

When cosmic rays (high-energy particles) from throughout the Universe collide with heavy atoms, nuclearrecoil causes gamma-ray emission.

Cosmic rays produced by high-energy astrophysics sources can reach any object in the Solar System, and appear to permeate our local region of space omnidirectionally. When they collide with Earth, they strike atoms in the atmosphere, creating particle and radiation showers at the surface. When they strike the heavy elements present on the Moon's surface, they can induce a nuclear recoil/reaction that winds up producing the high-energy gamma-rays we observe.

With no atmosphere or magnetic field, and a lithosphere rich in heavy elements, cosmic rays produce gamma-rays upon impacting the Moon.

Although the Sun doesn't typically generate either gamma-rays or cosmic-rays that account for what we see on the Moon, its complex magnetic field undergoes cyclical changes on an 11-year timescale. These changes can alter the gamma-ray flux from the Moon, over time, by up to about 20%.

If we had gamma-ray eyes, the Moon would always look "full" from any perspective.

With 7 panels of ever-increasing observing time, from 2 months up through 128 months, we can see how a gamma-ray image of the Moon becomes sharper and sharper over time. This image was taken by NASA's flagship gamma-ray observatory, Fermi, in energies of 31 MeV or higher. In these high-energy gamma-rays, the Moon indeed outshines the Sun.

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This Is The One Way The Moon Outshines Our Sun - Forbes

Milivoje M. Kostic, professor emeritus in theDepartment of Mechanical Engineering,and editor-in-chief of the Thermodynamics Section of Entropy journal, has been recently named as a topical collection editor of Foundations and Ubiquity of Classical Thermodynamics, after serving as a guest editor for three Entropy special issues in2013,2015 and 2018.

In 2018, Kostic also published a feature paper, Nature of Heat and Thermal Energy, and attended the16th International Heat Transfer Conference(IHTC-16) where he wasa panelist on the development of a new entransy theory. The inclusion to the panel has been influenced by Kostics publication related to theentransy concept and controversies, as well as his priorcollaboration with Chinese universities, starting withkeynote lecturesat the prestigious Tsinghua University.

Entropy is a monthly, peer-reviewed, open access, scientific journal covering research on all aspects of entropy and information theory. The journal publishes original research articles, communications, review articles, concept papers and more. Since Entropy became a mainstream, interdisciplinary journal at the end of 2015, it has diversified in several sections, which also include statistical mechanics, information theory, astrophysics and cosmology, quantum information and complexity, as well as in diverse special issues and more recently in topical collections.

Thermodynamics is a science of energy and entropy, considered by many to be among the most fundamental sciences. The phenomenological laws of thermodynamics have much wider, including philosophical, significance and implications than their simple expressions based on experimental observations they are the fundamental laws of nature. Classical thermodynamics crystallizes a diverse and complex reality to a fundamental cause-and-effect ubiquitous simplicity by its fundamental principles. That is why it is hard to understand thermodynamics the first time or the second time through.

Kostics research and scholarly interests are in fundamental laws of nature; thermodynamics and heat transfer fundamentals; the second law of thermodynamics and entropy; energy efficiency; conservation and sustainability; fluids-thermal-energy components and systems; and nanotechnology and nanofluids.

Kostic retiredfrom his regular NIU duties in 2014 to pursue his scholarly work and research.

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Quasars are some of the brightest objects in the Universe. The brightest ones are so luminous they outshine a trillion stars. But why? And what does their brightness tell us about the galaxies that host them?

To try to answer that question, a group of astronomers took another look at 28 of the brightest and nearest quasars. But to understand their work, we have to back track a little, starting with supermassive black holes.

A supermassive black hole (SMBH) is a black hole with more than a million solar masses. They can be much larger than that, too; up to billions of solar masses. One of these entities resides at the center of most galaxies, excluding dwarf galaxies and the like.

Theyre the result of the gravitational collapse of a massive star, and they occupy a spheroidal chunk of space from which nothing, not even light, can escape.

The Milky Way has one of these SMBHs. Its called Sagittarius A-star (Sgr A*) and its about 2.6 million solar masses. But Sgr A* is rather sedate for a SMBH. Other SMBHs are much more active, and theyre called active galactic nuclei (AGN.)

In an AGN, the black hole is actively accreting matter, forming a torus of gas that heats up. As it does so, the gas emits electromagnetic radiation, which we can see. AGNs can emit radiation all across the electromagnetic spectrum.

There are sub-classes of AGNs, and a new study focused on one of those sub-classes called quasars. A quasar is the most powerful type of AGN, and they can shine with the light of a trillion Suns. But some of these quasars are hidden behind their own torus, which blocks our line of sight. In studies of quasars, these ones are ignored or omitted, because theyre difficult to see.

But that creates a problem, because omitting them from the population of quasars means we might be missing something. It also means that one of the central questions around quasars might not be addressed properly.

The question is really multi-pronged: are these extremely bright AGN powered by moderate accretion onto extremely massive black holes? Or are they powered by extreme accretion onto more moderate mass black holes? Or maybe something else is going on. Are they powered by a host galaxy transitioning from a star-forming galaxy to something more sedate like an elliptical galaxy? By ignoring or omitting the quasars that are difficult to see, it makes finding any answers difficult.

A team of astronomers looked at 28 AGN that were both nearby and among the most luminous. Most of them happened to be in elliptical galaxies. The only criteria for choosing them was the intense activity in their nuclei. Their radio emissions span factors of tens of thousands, and their masses also cover a wide range. The astronomers wanted to find out if these bright AGN had any other distinctive qualities which would set them apart from lower luminosity obscured AGN.

Their are some intriguing and surprising results in this study. Some of the results seem to agree with other studies, while some go against the grain.

In the conclusion of their paper, the authors summarize their findings, and it seems that for now, at least, there is no clear explanation for these most luminous of quasars that shine with the light of a trillion stars.

We find that, as a group, our sample of some of the most luminous obscured AGN in BASS/DR1 does not exhibit any distinctive properties with respect to their black hole masses, Eddington ratios, and/or stellar masses of their host galaxies.

They also point out that the host galaxies are mostly all ellipticals, a surprising find. If this finding can be corroborated by other researchers, it may lend some indirect evidence in support of the popular idea that epochs of intense SMBH growth are linked to the transformation of galaxies from (star-forming) disks to (quenched) ellipticals (i.e., through major mergers).

There are 21 researchers behind this study, at institutions including the Harvard and Smithsonian Center for Astrophysics, Tel-Aviv University, Kyoto University, JPL, the Naval Observatory, the ESO, and many others. The data for their study comes from the 70 month Swift/BAT all-sky survey, and with observations using the Keck, VLT, and Palomar observatories. The study is titled BAT AGN Spectroscopic Survey XIII. The nature of the most luminous obscured AGN in the low-redshift universe. Its published in the Monthly Notices of the Royal Astronomical Society.

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Some Quasars Shine With the Light of Over a Trillion Stars - Universe Today

When he was growing up, Jonathan LeyVa thought hed follow his passion for race cars and pick a profession in automotive engineering. Instead hes working on what will become one of the worlds most sensitive searches for dark matter, the invisible substance that accounts for more than 85%of the mass of the universe.

LeyVa works in a clean room at the Department of Energys SLAC National Accelerator Laboratory, where crews are building detectors for the latest in a series ofSuper Cryogenic Dark Matter Search, or SuperCDMS,experiments. As an early-career physicist, part of his job is keeping track of how much exposure to cosmic rayshigh-energy particles falling in from spacethe detector components are getting. Researchers want to keep that exposure to a minimum because it could harm their ability to detect dark matter later on.

Ive been interested in cosmology since my senior year in college, LeyVa says, so Im lucky enough to be able to contribute to an exciting project like this at the frontline of dark matter research.

As a freshman at Santa Clara University, LeyVa started out in mechanical engineering, following his childhood dream of doing something with cars. But he soon realized that the field wasnt for him. Inspired by his dad, who holds a physics degree, and by his physics professor at Santa Clara, he began studying physics during his sophomore year.

Having been committed to engineering at first, making this switch was quite daunting, LeyVa says. But he quickly got into the physics world and completed his undergraduate studies in 2017.

Around the time of his graduation, Santa Clara Professor Betty Young suggested that LeyVa spend some time inKent Irwins labat Stanford University, where Young is a visiting scholar. There he learned about SQUIDssuperconducting quantum interference devices used in precision sensors, including those for dark matter searches with SuperCDMS.

This experience got LeyVa hooked on dark matter, whose nature is still unknown and one of the biggest mysteries of modern physics.

He spent the following year with Blas Cabreras team at Stanford, looking for ways of making future SuperCDMS detectorsmore sensitive to lightweight dark matter particles. In 2018he became a member of the SuperCDMS group at SLACs and StanfordsKavli Institute for Particle Astrophysics and Cosmology, which is building detector towers for the current version of the experiment; its scheduled to begin its hunt for dark matter at the Canadian underground lab SNOLAB in the early 2020s.

Nowadays, LeyVa spends a lot of his time in a clean room at SLAC, supporting the SuperCDMS team in assembling the detector towers.

SuperCDMS SNOLAB will initially have four towers, each containing a stack of six silicon and germanium crystals and a bunch of sensitive electronics. Cooled down to almost absolute zero temperature, the crystals will vibrate ever so slightly if a dark matter particle rushes through them, and its these tiny vibrations that the experiment will be looking for.

A major challenge in building the experiment is that the crystals and other detector components are sensitive to particle showers produced when cosmic rays hit the atmosphere. These showers cause unwanted background signals that could make it hard to pick up potential dark matter signals. Thats why the experiment at SNOLAB will operate 6800 feet underground, where its protected from those effects.

It also means that the SuperCDMS team must limit how much detector components are exposed to cosmic rays during the construction of the experiment. Components for the detector towers, for example, are kept three stories underground in a tunnel at Stanford, where they are relatively protected. For the tower assembly and testing, they are brought to SLAC, but each tower can spend only a total of a week at the surface. LeyVa is like a cosmic-ray bookkeeper, closely tracking and logging the number of hours that crystals and hundreds of other detector components are being handled at the lab. Working closely with the teams software developers, hes maintaining and improving the database for that task.

In addition, hes involved in a number of other parts of the project, including noise studies of the system that will collect SuperCDMS data and R&D for future generations of the experiment.

Working on SuperCDMS is just the type of hands-on experience LeyVa enjoys. He loves to experimentat work and in his spare time. It seems that I have too many hobbies for my own good, he says jokingly.

In college, LeyVa volunteered on film crews, which involved him in videography, lighting and acting for several productions. As a media systems technician at his university he set up large-scale sound and video systems for important events. One of the most memorable ones, he says, was a talk by actor Martin Sheen.

Sheen talked about social justice and activism, and I remember his presence created quite a buzz at SCU, he says. I grew up seeing him in some of my favorite movies. He seemed to be a very warm, kind person.

LeyVa is also into photographyan interest that was sparked by his parents. In the early 2000s up to about 2010-ish both my parents ran an advertising agency, taking jobs from some Silicon Valley tech companies. My dad would do photography and my mom would do editing work and graphic design, he says. My parents and my activities in college were influences that may have inspired me to fiddle with instruments in more depth.

In SLACs clean room he continues to find inspiration. SuperCDMS allows him to work on many sides of the projects science and technology, which he considers to be a great learning experience.

Right now, LeyVas planning his next steps in life, such as going to grad school. Particle physics with an emphasis on cosmology and astrophysics is what interests me the most, so becoming involved in cutting-edge cosmological research has been a dream come true for me, he says. Its motivating me to take it to the next level and follow in the footsteps of the great researchers Im working with.

Editor's note: This article is adapted from anarticleoriginally published by SLAC National Accelerator Laboratory.

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A day in the life of a cosmic-ray 'bookkeeper' - Symmetry magazine

Missouri S&T has joined the Hobby-Eberly Telescope Dark Energy Experiment (HETDEX) as one of 11 international institutions that are collaborating to define the force causing the accelerated expansion of the universe.

The cosmic acceleration is one of the biggest mysteries in our fundamental physics, says Dr. Shun Saito, cosmologist, assistant professor of physics and leader of Missouri S&Ts HETDEX research group.

To explain this phenomenon we believe began 5 billion years ago, we must introduce an unknown energy component with negative pressure into the universe. That component is what we now call dark energy, Saito says.

Two independent scientific teams unexpectedly discovered cosmic acceleration in 1998. They had initially set out to prove the deceleration of the universe based on a common belief that the universe was dominated by matter, and that its expansion would be slowed down by the pull of gravity. Their discovery that the expansion was not slowing down, but actually accelerating, led to the 2011 Nobel Prize in Physics for three members of those teams.

Saito says the best prevailing model to define dark energy is the cosmological constant Einsteins concept of the energy density or vacuum energy of space he introduced in 1917 when he wantedto stop the universe from collapsing.

HETDEX is stepping into unexplored territory of the universe, says Saito. The discovery potential ofthe experiment is huge we may be able to find that dark energy isnt Einsteins cosmological constant, and this would require a newunderstanding of fundamental physics.

To pursue this quest, Missouri S&T recently joined HETDEX through a memorandum of understanding between the University of Missouri Board of Curators on the recommendation of S&Ts physics department, and the University of Texas at Austin on behalf of its McDonald Observatory, located in the Davis Mountains of West Texas.

The McDonald Observatory contains the Hobby-Eberly Telescope (HET), one of the worlds largest optical telescopes. It has a primary mirror made up of 91 hexagonal segments, and was recently upgraded to a usable aperture of 10 meters with a new wide-field instrument suite, specifically for the HETDEX project.

The immense light-gathering power of this telescope allows us to map out one million distant galaxies that are 9 to 11 billion light-years away, Saito says. Saito will contribute to HETDEX by analyzing the gigantic three-dimensional galaxy maps produced from a set of 78 spectrographs mounted on HET.

Intensity mapping is a novel technique for observing the large-scale structure of the universe its our future, says Saito. It gives us a more efficient and powerful way to extract cosmological information from the data. Even though the technique is mainly used by radio astronomers, we hope to pioneer it in the optical field with HETDEX.

HETDEX observations began in December 2017, and Saito expects the project to continue for about three years.

Over the last year, Missouri S&T has focused on further advancing its astrophysics program.

Saito joined S&T in January from the Max-Planck-Institute for Astrophysics in Germany, where as a postdoctoral researcher, he contributed his cosmological mapping expertise to HETDEX and other spectroscopic, or light-measuring, galaxy surveys. He also contributed to the Baryon Oscillation Spectroscopic Survey in the Sloan Digital Sky Survey-III where space-time measurements were used to investigate dark energy.

Dr. Siddhartha Gurung-Lopez from Centro de Estudios de Fsica del Cosmos de Aragn in Spain recently joined S&Ts HETDEX research group to simulate realistic, computer-generated galaxy populations to compare to the HETDEX observations.

Missouri S&Ts astrophysics program is off to an excellent start, says Dr. Thomas Vojta, chair of the physics department and Curators Distinguished Professor of physics. With our participation in HETDEX and in the LIGO (Laser Interferometer Gravitational-wave Observatory) Scientific Collaboration, we now have cutting-edge research groups in gravitational wave physics and in cosmology. S&T is keeping its eyes wide open to the sky.

HETDEX is a collaboration of The University of Texas at Austin,Pennsylvania State University, Texas A&M University, Ludwig MaximilianUniversity of Munich, Leibniz Institute for Astrophyics Potsdam (AIP), Max PlanckInstitute for Extraterrestrial Physics, Max Planck Institute for Astrophysics, Institutefor Astrophysics in Gttingen, The University of Oxford, The University ofTokyo and Missouri University of Science and Technology. Financial support isprovided by the State of Texas, the United States Air Force, the NationalScience Foundation, partner institutions and the generous contributions of manyprivate foundations and individuals.

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Missouri S&T joins dark energy experiment to solve accelerating cosmos mystery - Missouri S&T News and Research

AstronomyHow a discovery at a Hawaii volcano sparked a project with a history unlike anything else on campus

The unassuming observatory dome on the roof of the Physics and Biology Research Building, while unused today, has a storied past. Photo by Jackie Ricciardi

Every day, hundreds of BU students walk down Cummington Mall, unaware that they are passing by a fascinating and unique campus relic, with a story full of drama, mystery, near-disaster, and earth-shattering scientific intrigue.

The unassuming observatory dome on the roof of the Physics and Biology Research Building (PRB) has a storied past: it was built to house a telescope that was eventually used at the South Pole.

The story of this observatory began in 1990 when astronomers at Mauna Kea, a mostly underwater volcano on the island of Hawaii, detected carbon in interstellar clouds that was 10 times brighter than anyone had expected. Interstellar clouds are accumulations of gas, dust, and plasma between star systems in a galaxy. Astronomers can determine the chemical compositions of these clouds by studying the radiation they emanate. The unexpected abundance of carbon detected on Mauna Kea was excitingit could point to something new in the field of astronomy.

The notion was that there may be a lot of atomic carbon that weve never properly mapped, says Thomas Bania, a College of Arts & Sciences professor of astronomy. Carbon is a very important atomic element, and if theres a whole lot of carbon in atomic form that we dont know about, it completely changes the way we study the chemistry of the interstellar medium and the chemistry of molecular clouds, things like that. Detecting that much more carbon would radically change our understanding of the composition of significant portions of the Milky Way Galaxy, transforming our understanding of galactic evolution, the formation of stars and planets, and perhaps even the origin of life in the universe.

Eager to follow this lead, Anthony Stark, an astrophysicist at the Harvard Smithsonian Center for Astrophysics, teamed up with Bania and a team of astronomers from BU and Harvard to create the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) project. Their group included BU astronomy doctoral students Maohai Huang (GRS00), Alberto Bolatto (GRS01), James Ingalls (GRS98), and undergraduate Edgar Castro (ENG95). Together, they set out to design and build a telescope from scratchone that they would eventually send all the way down to the South Pole for carbon observations.

Observational astronomers run into all sorts of issues when trying to operate a telescope in warmer environments: high wind speeds can shake the instruments, rapid temperature fluctuations cause metal and glass in the telescope to expand and contract, wet weather can damage the sensitive instrumentation, and nosy animals or errant birds can interfere with the telescope.

But these arent issues at the South Pole. It may not be a livable environment, but for over a century, astronomers have been conducting science in this inhospitable place, because with all the inconveniences of moderate climates, scientists have decided the benefits of what they might learn there make getting a bit cold worthwhile.

From 1990 to 1992, the AST/RO telescope was built from scratch at Bell Laboratories in New Jersey and BUs Scientific Instrument Facility in the PRB basement. Its design is called offset Gregorian: once light enters the telescope, it bounces off four mirrors that direct it into a room below, called a Coud room, where it is focused into an image.

As the telescope was being built, a team of BU Facilities Management & Planning workers constructed the test dome on the PRB roof. This was an ideal place to test the telescope since the rooftop had a clear view of the southern horizon (the Life Science & Engineering Building wasnt there yet). One challenge, though, would be getting the telescope up there. The elevator goes only as high as the fifth floorfrom there you have to climb another flight of stairs and then a ladder to get to the porthole that opens onto the roof. The AST/RO researchers made this climb every time they had to get to the observatory. That ladder is still the only way to get to the roof.

There was no way they could bring the telescope in pieces, one by one, up the ladder and through the two-foot-by-two-foot porthole. So the team installed a small crane inside the dome and used it to lift several of the telescope pieces from the fifth floor, through a series of hatchwaysand through a biology labto the observatory. The biggest telescope pieces had to be hoisted onto the roof from a crane outside the building.

Once everything was assembled on the roof, the team spent 18 months testing the instrumentation. Huang remembers spending many long nights at the test site, even taking naps in the control room below the telescope. But every so often, he would wander up to the rooftop dome and enjoy a few quiet moments in the Boston morning. There is nobody there, of course, he says, as the sun is just beginning to crest over the city skyline in the east, and you can see very faryou can see the Charles River, and everything.

In 1995, the AST/RO telescope was finally ready for the South Pole. The team packed it up in a green-painted wooden crate (nicknamed the Green Monster). Its journey to the South Pole took three weeks and multiple modes of transportation: Boston to Los Angeles via truck, Los Angeles to McMurdo Station in Antarctica by ship, then McMurdo to the Amundsen-Scott South Pole Station aboard a C130 military plane.

But it did not go gentle: on the first leg of the trip, the truck carrying it crashed on a highway near Little Rock, Ark. Bania recalls going down to assess the damage with James Jackson, a CAS adjunct professor of astronomy. We had the telescope, all of its computers, all of its electronics, all of the spares, all of the tools that it was going to take to put it back together, all of the documentation for an entire state-of-the-art high-frequency radio observatory in one truck, says Bania. He and Jackson had to decide if it was worth the risk to send the telescope down to the South Pole, or if they should just bring it back to Boston and take stock of the damage there, losing a year in the process.

They decided to send it down to Antarctica. Fortunately, their gamble paid offthe telescope arrived in working condition.

The AST/RO telescope operated at the South Pole from 1995 to 2001. Bania and his students went down every year during the Antarctic summer (winter in the Northern Hemisphere) to perform maintenance and keep it operational.

In the end, though, the project was deemed a flop. After 10 years of work, it turned out that, no, carbon was brighter for a different reasonand so there wasnt this vast reservoir of atomic carbon, Bania says. And proving a negative never leads to a sexy press release.

With that, AST/RO was unceremoniously boxed back up and left in a graveyard of other abandoned scientific instruments at the South Pole. Its now probably buried under ice.

For those who spent hours, days, weeks, and years of their lives on the project, however, it was hardly a flop; all four BU grad students who worked on it got their doctorates and are still doing astronomy research. Huang, for example, is a research professor at the National Astronomical Observatory of China, where he works on the science operation and data processing system for astronomical systems, including the Herschel Space Observatory. What I learned from AST/RO really directly goes into what Im working on now, Huang says. Controlling AST/RO was as difficult as controlling a telescope in space, he says: both are hard to access, so youd better make sure things work the first time. If something breaks, its going to take a very long time to fix.

And, almost 30 years later, the AST/RO test dome remains atop the southwest corner of PRB, a monument to the teams decade of work.

For those researchers like Bania, it stirs up mixed memories. On bad days, I think I wasted 10 years of my life, he says. On good days, I think, well, you know, I had the opportunity to build an observatory from the ground up and operate it. Not many people can say that.

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The Secret History of BU's PRB Observatory and the Telescope It Was Built to House | BU Today - BU Today

Astronomers have spotted three supermassive black holes (SMBHs) at the center of three colliding galaxies a billion light years away from Earth. That alone is unusual, but the three black holes are also glowing in x-ray emissions.

This is evidence that all three are also active galactic nuclei (AGN,) gobbling up material and flaring brightly.

This discovery may shed some light on the "final parsec problem," a long-standing issue in astrophysics and black hole mergers.

Astronomers found the three SMBHs in data from multiple telescopes, including the Sloan Digital Sky Survey (SDSS,) the Chandra X-ray Observatory, and the Wide-field Infrared Survey Explorer (WISE.)

The three black holes are wrapped up in an almost unimaginably epic event; a merger of three galaxies. These triplet mergers may play a critical role in how the most massive black holes grow over time.

The astronomers who found it were not expecting to find three black holes in the center of a triple-galaxy merger.

"We were only looking for pairs of black holes at the time, and yet, through our selection technique, we stumbled upon this amazing system," said Ryan Pfeifle of George Mason University in Fairfax, Virginia, the first author of a new paper in The Astrophysical Journal describing these results.

"This is the strongest evidence yet found for such a triple system of actively feeding supermassive black holes."

Triple black hole systems are difficult to spot because there's so much going on in their neighbourhood. They're shrouded in gas and dust that makes it challenging to see into. In this study, it took several telescopes operating in different parts of the electromagnetic spectrum to uncover the three holes. It also took the work of some citizen scientists.

They're not only difficult to spot, but rare.

"Dual and triple black holes are exceedingly rare," said co-author Shobita Satyapal, also of George Mason, "but such systems are actually a natural consequence of galaxy mergers, which we think is how galaxies grow and evolve."

(Hubble/Pfeifle et. al., arXiv, 2019)

The SDSS was the first to spot this triple-merger in visible light, but it was only through Galaxy Zoo, a citizen science project, that it was identified as a system of colliding galaxies.

Then WISE saw that the system was glowing in the infrared, indicating that it was in a phase of galaxy merger when more than one of the black holes was expected to be feeding.

The Sloan and WISE data were just tantalizing clues though, and astronomers turned to the Chandra Observatory and the Large Binocular Telescope (LBT) for more confirmation. Chandra observations showed that there were bright x-ray sources in the center of each galaxy. That's exactly where scientists expect to find SMBHs.

More evidence showing that SMBHs were there arrived from Chandra and NASA's Nuclear Spectroscopic Telescope Array(NuSTAR) satellite. They found evidence of large amounts of gas and dust near one of the black holes.

That's expected when black holes are merging. Other optical light data from the SDSS and the LBT provided spectral evidence that's characteristic of the three SMBHs feeding.

(NASA/CXC/NGST)

"Optical spectra contain a wealth of information about a galaxy," said co-author Christina Manzano-King of University of California, Riverside. "They are commonly used to identify actively accreting supermassive black holes and can reflect the impact they have on the galaxies they inhabit."

With this work, the team of astronomers have developed a way to find more of these triple black hole systems.

"Through the use of these major observatories, we have identified a new way of identifying triple supermassive black holes. Each telescope gives us a different clue about what's going on in these systems," said Pfeifle. "We hope to extend our work to find more triples using the same technique."

They may have also shed some light on the final parsec problem.

The final parsec problem is central to our understanding of binary black hole mergers. It's a theoretical problem that says when two black holes approach each other, their excessive orbital energy stops them from merging. They can get to within a few light years, then the merging process stalls.

When two black holes initially approach each other, their hyperbolic trajectories carry them right past each other. Over time, as the two holes interact with stars in their vicinity, they slingshot the stars gravitationally, transferring some of their orbital energy to a star each time they do it. The emission of gravitational waves also decreases the black holes' energy.

Eventually the two black holes shed enough orbital energy to slow down and approach each other more closely, and come to within just a few parsecs of each other.

The problem is, as they close the distance, more and more matter is ejected from their vicinity via sling-shotting. That means there's no more matter for the black holes to interact with and shed more orbital energy. At that point, the merging process stalls. Or it should.

Yet astrophysicists know that black holes merge because they've witnessed the powerful gravitational waves. In fact, LIGO (Laser Interferometry Gravitational-Wave Observatory) is discovering a black hole merger about once a week. How they merge with each other at the end is called the final parsec problem.

The team behind this study thinks that they might have an answer. They think that a third black hole, like they've observed in this system, could provide the boost needed to get two holes to merge.

As a pair of black holes in a trinary system approach each other, the third hole could influence them to close the final parsec and merge.

According to computer simulations, about 16% of pairs of supermassive black holes in colliding galaxies will have interacted with a third supermassive black hole before they merge.

Those mergers would produce gravitational waves, but the problem is that those waves would be too low-frequency for LIGO or the VIRGO observatory to detect.

(ESA/NASA/LISA)

To detect those, scientists may have to rely on future observatories like LISA, ESA/NASA's Laser Interferometer Space Antenna. LISA will observe lower frequency gravitational waves than LIGO or VIRGO and is better-equipped to find super-massive black holes merging.

The paper presenting these results is titled "A Triple AGN in a Mid-Infrared Selected Late Stage Galaxy Merger."

This article was originally published by Universe Today. Read the original article.

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Astronomers Find a Place With Three Supermassive Black Holes Orbiting Each Other - ScienceAlert

Renowned cosmologist speaks about major scientific discovery in her latest book

By Sara Abdelouahed, Collegian CorrespondentOctober 1, 2019

On Thursday, Sept. 26th, the Commonwealth Honors College began a year-long series of events celebrating its 20th anniversary at the University of Massachusetts. This preliminary event, the Williamson Lecture, featured world-renowned author and cosmologist Janna Levin.

The focus of Levins talk was her newest book, Black Hole Blues and Other Songs from Outer Space, which explores the discovery of gravitational waves produced by black holes. Her knowledge and connections to those involved in the discovery allowed her to bring the story of the 50-year endeavor to life.

Honors College Dean Gretchen Gerzina introduced Levin with a brief summary of her background and experience. Levin is well known in the astronomy community for her work in understanding black holes and the cosmology of extra dimensions. She previously presented the NOVA show Black Hole Apocalypse on PBS, the shows first female presenter in 35 years. Along with her newest release, Levin has now published three books.

According to Gerzina, she is the rock star of astrophysics.

Her presence in the scientific community is known even to college students, including freshman physics major Garrett Mann. Mann had previously seen Levin on a YouTube show with astrophysicist Neil deGrasse Tyson. Manns curiosity and desire to know how [blackholes] work drew him to the event to hear her speak in person.

Other students echoed his desire to learn more. Freshman biochemistry major Aurora OConnor came without prior knowledge of the subject matter.

I know nothing about black holes, OConnor said. Maybe I should learn something about them.

Levin highlighted the exciting ups and downs of the scientific breakthrough using metaphors, anecdotes, and humor, allowing listeners of all backgrounds to comprehend the significance of the feat.

When asked about her favorite aspect of talking to college students, Levin said that everyone was really engaged. Its so fun when people are that present and curious and energized.

Students were eager to ask questions after the discussion, quickly lining up for the opportunity to talk to Levin and have their copies of her book signed. Amherst Books sold Levins newest publication at the event.

Colby Pratt, a freshman astronomy major at the University, said that her personal interest drew her to the event. Not only did she want to better understand black holes, but she [wanted] to be able to share that with other people.

Levin shares a similar philosophy.

[Physics] is like a gift, it belongs to you, she explained. Its something you inherit as soon as you learn it and then its yours to teach to somebody else. She said that the ability to share learned information with others was something that [she] found just incredibly, overwhelmingly exciting.

The 20th Anniversary celebration of the Commonwealth Honors College continues on Oct. 1 with a lecture from Banu Subramaniam, titled A Scientific Renaissance: Gender, Race, and the Practice of Science.

Sara Abdelouahed can be reached at [emailprotected].

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Sounds of space: Janna Levin kicks off celebration of the 20th anniversary of the Commonwealth Honors College - The Massachusetts Daily Collegian

Enlarge / Bobby Braun, seen in Mission Control at NASA's Jet Propulsion, will move to the lab in early 2020.

NASA's Jet Propulsion Laboratory has found a new leader for its Solar System exploration program, and the choice of Bobby Braun signals a willingness to adapt to the changing world of aerospace.

Braun, an engineer who specializes in cutting-edge technology, will join the NASA laboratory from the College of Engineering and Applied Science at the University of Colorado Boulder, where he served as dean. The Jet Propulsion Laboratory (or JPL) has led NASA's efforts to explore the Solar System with uncrewed spacecraft from the beginning.

"JPL has always been a special place to me," Braun said in an interview. "It is the center of our nation's planetary exploration efforts, with flagship missions that have rewritten our textbooks." Those missions have included the Voyager excursions through and beyond the Solar System, dedicated probes to Jupiter and Saturn, and multiple landings on Mars.

JPL's preeminence as the world leader in planetary probes is not in doubt, but several threatssuch as budget pressures and competition from the Johns Hopkins University Applied Physics Laboratory for missionsmay have led Center Director Michael Watkins to conduct a broad search for a new leader of the lab's programs for Solar System exploration.

In a Monday memo to JPL employees announcing Braun's appointment to the position, effective January 15, 2020, Watkins wrote, "Over the past several months, I have conducted a national search for the right leader to carry forward implementation of our present planetary exploration missions and, in concert with the external community, plan the future of this enterprise which is critical to the Lab, NASA, and the nation."

Braun has experience working with JPL, as well as for NASAfrom 2010 to 2011, he served as the NASA chief technologist and created what is now the NASA Space Technology Mission Directorate. But he also has spent half of his career in academia, so he is attuned to the needs of scientists who propose and lead these exploration missions, and he also has a reputation for working with private spaceflight companies to harness commercial ideas to improve government-led projects.

For example, Braun was heavily involved in setting up a partnership between JPL, NASA, and the rocket company SpaceX to use its Red Dragon proposal for the scientific exploration of Mars. This ultimately did not happen for a number of reasons, including the decision by SpaceX to move on to building the much larger Starship vehicle. But it is an example of Braun working beyond traditional means of Solar System exploration."Sometimes it takes somebody from the outside to bring organizations together around these kinds of ideas," Braun said.

As part of Braun's hiring, JPL will likely undergo a reorganization, according to Watkins' memo. The lab isconducting a study about merging significant portions of the existing Mars Exploration Directorate into the Solar System Exploration Directorate. This would bring about half of JPL's exploration activities under Braun's leadership of Solar System programs. The other half includes Earth science, astrophysics, and work JPL does for other NASA centers.

Braun will have to hit the ground running. The lab's next major mission, the Mars 2020 rover, is due to launch on July 17. Braun will also superintend work on an ambitious orbital mission to the Jupiter system focused on its icy moon Europa as well as the Psyche mission to a metallic asteroid. Both could launch in the early 2020s depending on budget and work schedules.

Beyond that, Braun said he hopes to further NASA's efforts to possibly find life elsewhere in the Solar System and help ensure that a long-awaited Mars Sample Return mission finally happens.

Excerpt from:

NASA signals openness to change with new Solar System exploration hire - Ars Technica