Astrophysics for People in a Hurry, by Neil deGrasse Tyson – Times Higher Education (THE)

Plato had it right when he said that astronomy compels the soul to look upwards. The universe makes for beautiful images and stories littered with superlatives. Astronomers draw on most of modern physics, from gravitation to quantum mechanics, and drive new discoveries in regimes that we could never reach in the laboratory. We develop cutting-edge instrumentation for telescopes on Earth and in space. And our field has a history spanning thousands of years, ever since those first souls looked up and marvelled at the view.

Neil deGrasse Tysons aim is, on the face of it, daunting to convey something of all of this to a level of foundational fluency in only 200 pages. But the presenter of the radio programme StarTalk and the television documentary series Cosmos: A Spacetime Odyssey, one of the most experienced science communicators around, is up to the challenge.

The book is adapted from a series of essays originally written in 1998-2007, and this shows in the format: theres some repetition, and the flow between chapters feels rather random. The upside is that each chapter stands alone, perfect for the busy reader who wants to dip in and out. The breadth of topics is excellent, and includes the Big Bang, dark matter, dark energy, the formation of the elements and the search for life elsewhere in the universe. There is no stinting on physics, and astronomers get some stick for the century-long gap between the discovery of radiation beyond the visible and the development of telescopes in these wavebands. The style is vintage Tyson engaging, chatty and littered with historical and linguistic anecdotes (including a lovely reference to petunias, in a nod to the late, great Douglas Adams).

There are some surprising omissions. There is relatively little on the birth, life and death of stars. The stars dominate our night sky, and Im still amazed by the fact that we understand the processes that differentiate our Sun from the red supergiant Betelgeuse and the white dwarf Sirius B. Supermassive black holes, such as the monster in the centre of our galaxy, get barely a mention, and the chapter on telescopes does not do justice to the full range of new technology at our disposal. However, this is understandable in a slim volume.

Although many scientists are namechecked, I was disappointed that only three women made the cut: Vera Rubin (dark matter pioneer), Jocelyn Bell (discoverer of pulsars) and Carolyn Shoemaker (of comet fame). Stellar physics without Annie Jump Cannon or Cecilia Payne-Gaposchkin, the cosmic distance scale without Henrietta Swan Leavitt, radio astronomy without Ruby Payne-Scott? This is a book that aims to inspire the next generation of scientists, and women have played, and continue to play, a major role in our field.

Tyson opens the book by discussing the allure of astronomy in popular culture. He takes a more sombre view at the end, with a sober assessment of our place in the cosmos and a plea to embrace this cosmic perspective. In an era where it feels that we have to defend science, it is the right way to finish: marvel at the universe, enjoy puzzling it out, and do your utmost to protect our neighbourhood even if youre busy.

Anna Watts is associate professor of astrophysics, University of Amsterdam. She works on neutron stars and the next generation of X-ray space telescopes.

Astrophysics for People in a Hurry By Neil deGrasse Tyson W. W. Norton, 224pp, 14.99 ISBN 9780393609394 Published 2 June 2017

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Astrophysics for People in a Hurry, by Neil deGrasse Tyson - Times Higher Education (THE)

STT Astrophysics Conference To Look At Black Hole Collisions – St, Thomas Source

Black holes merging (Illustration by Aurore Simonnet at Sonoma State University, via http://www.apod.com)

The University of the Virgin Islands is hosting a conference on astrophysics this week, looking at the newly-confirmed existence of gravitational waves sent across the universe when two black holes- bodies of such immense mass and density that no light can escape collide.

Taking place June 5-9, the conference: Generation-GW: Diving into Gravitational Waves, is one of two astronomy conferences this summer sponsored by UVIs College of Science and Mathematics and the Telemann Observatory. The second conference, Unveiling the Physics Behind Extreme AGN Variability will take place from July 11-14. Both conferences are on crucial astronomy breakthroughs

over the last few years.

We are establishing a legacy, and these events will improve the recruitment of Virgin Islands students to study physics and astronomy at UVI, Antonino Cucchiara, assistant professor of physics said in a statement from UVI.

The conferences will also demonstrate how research and activities undertaken at UVI can benefit the community, he added.

Groups of astrophysicists from around the world are coming to talk at the June conference on gravitational waves, which are widely considered to be the greatest discovery so far of 21st century astronomy. This phenomenon describes ripples in the curvature of space-time that propagate outward from their source at the speed of light- the fastest speed anything can go. Light goes about 186,0000 miles per second. Their discovery confirms a 100 year old theory of Albert Einsteins.

The other discovery to be discussed by more than 50 astronomers at the July conference is Fast Variable Active Galactic Nuclei. The center of every galaxy has a super massive black holewith the mass of millions of suns.When a star has more than about 10 times the mass of our sun, when its fuel runs out and fusion is no longer stoking the stars fires, the gravity of all that mass will crush all the atoms down to a point were it all collapses into a point- a singularity. The gravity is so intense around it that at some point not even light can get out, if it gets too close. As matter falls into it, it speeds up, and is crushed. As the matter falls, it spins faster and faster, forming a disk that heats up to unimaginable temperatures, producing energy that is observable in optical, X-ray, gamma-ray radiation.

Most or all galaxies have really big black holes at their center. Our galaxy; the Milky Way galaxy, has one named Sagittarius A* that is about four million times the mass of the sun. How these supermassive black holes came to be is still being debated.

Some galaxies have little activity- nothing is falling in for long stretches of time- they are inactive. Some have constant activity- a regular disk that constantly radiates intense energy. And some are variable. The July conference will focus on Fast Variable AGNs, which radiation changes quickly in time and are therefore difficult to observe in detail.

Both conferences are only open to paid registrant due to space limitations. There will, however, be a specific talk designed for public-access to be held at UVIs ACC (Administration and Conference Center) on Thursday June 8th at 7 p.m. Admission is free and open to everyone.

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STT Astrophysics Conference To Look At Black Hole Collisions - St, Thomas Source

Company Seven | Astro-Physics 13cm f8 EDT Telescope

The 130mm f8 StarFire EDT is a very portable, lightweight refractor with a Super ED triplet objective that is highly corrected for false color (chromatic aberration). The color error is lese than 0.01% from 706nm to 450 nm, compared to a two element Fluorite apochromat with 0.05%, or a Doublet Achromat with 0.45% color error over the same spectral range. In an age when Fluorite is being marketed as the best lens material for fast refractors, it is significant that Astro-Physics has developed a non-Fluorite objective with 5 times better chromatic aberration at a fraction of the cost of Fluorite. Super ED glass (ED stands for extra low dispersion, Vd> 90) is a real glass, not a crystal like Fluorite. ED is a harder, less fragile material with a much lower expansion coefficient than Fluorite. Unlike Fluorite, ED glass is not affected by atmospheric contaminants and acids. It is for these reasons that all the world's major camera manufacturers are incorporating ED glass into their best lenses.

The extremely high color correction of the Super EDT design allows the construction of a relatively short-focus objective that is superior to long-focus achromats in contrast and definition of subtle planetary detail. The EDT lens is also perfectly matched to the characteristics of the fine grained Technical Pan emulsions which have their peak sensitivity at 45nm. With our matching accessories, you can create impressive astrophotos with CCD cameras, or on 35mm and 6 x 7cm film formats.

The optical design of the 130mm EDT objective consists of a positive element of ED glass surrounded by two matching hard crown meniscus lenses. The two outer elements are chosen so that the combination is free of coma, spherical aberration and other higher-order aberrations. All surfaces are spherical, which results in a very smooth overall figure. Under steady viewing conditions, you will see a hard white Airy disc at focus surrounded by the first diffraction ring. Inside and outside of focus, you will see an evenly illuminated, expanded disc with concentric Fresnel rings, the outermost ring brighter and wider than the rest. The two air-glass surfaces have multi-layer anti-reflection coatings that result in overall light transmission greater than 97% in peak visual wavelengths.

Our superb Astro-Physics focuser is a very finely crafted unit with several unique features. The components are machined on Astro-Physics' CNC to extremely high tolerances, assuring that there is no wiggle between the drawtube and housing. More than a dozen knife-edge baffles are machined into the wall of the drawtube and painted flat black in order to maximize contrast by essentially eliminating any internal reflections. We inside diameter (I.D.) of the drawtube is 2.7" which allows the avid astrophotographer to use a medium format camera to capture images in a 6 x 7cm format with minimal vignetting. You can use standard accessories with the 2" and 1.25" adapters. Recessed brass locking rings are installed at each thumbscrew location. As you tighten each thumbscrew, the brass locking ring damps onto the part that has been inserted. Consequently, your focuser drawtube and 2" and 1.25" accessories are held securely in place. This is particularly important considering the heavy and expensive accessories that you may use. As an added advantage, the brass will not mar the surface of your accessories.

The 130EDT optical design is ideal for astrophotography with small- and medium-format cameras. The widefield coverage in the 6x7 photographic format will record gorgeous images of a wide variety of objects such as the Andromeda Galaxy and the Lagoon and Trifid Nebulas. The negatives contain so much finely resolved detail that you can enlarge a small portion to feature one particular aspect of the object, i.e. the Gulf of Mexico portion of the North American Nebula. One of the finest solar eclipse photographs of the corona was taken with the 130 EDT StarFire refractor in July 1991. This photo and other deep sky photos that were taken with our 5" f8 StarFire have appeared on the cover of numerous astronomical publications around the world.

Diagonals and Binocular Viewers: Prism diagonals have aberrations which degrade image quality. Since this is especially noticeable in telescopes with fast focal ratios, we recommend the 2" Precision Mirror Diagonal. If you use a binocular viewer (which has prisms), then place a Barlow between the focuser and binocular viewer.

Eyepieces: Plossls, Orthoscopics, and Widefield eyepieces show sharp images only in the center of the field. These are fine as long as you realize this limitation. If you object to astigmatic images at the edge of the field, we recommend the TeleVue Nagler and Panoptic eyepieces. These oculars have the best flat field images and will bring out the most in your 130 StarFire EDT. Use our 2x (2") Barlow to double your magnification.

Right: Company Seven ATA Case custom fitted for a Astro-Physics 13cm EDT Apochromat Telescope with 2.7 inch Focuser (65,974 bytes). Click on image to see enlarged view (215,942 bytes).

Features include:

Left: Astro-Physics Model 900 Mount in optional Company Seven ATA case. Case 1 of 2 shown here, with Declination housing (left side shown) with GTO Keypad Controller and Counterweight Shaft (94,326 bytes).

Please refer to the brochure for descriptions of these items and additional accessories.

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Company Seven | Astro-Physics 13cm f8 EDT Telescope

Book Review: ‘Astrophysics for People in a Hurry’ – Dan’s Papers

Scientists are confidently predicting that the two stars of binary system KIC 9832227, about 1,800 light years away in the northern wing of the Cygnus constellation, will collide with each other sometime between 2021 and 2023, creating a spectacular astronomical eventa red nova, the brightest star in the night sky, visible on earth even without a telescope. Theres no denying itits science. The good thing about science, says astrophysicist, Director of the Hayden Planetarium in New York, StarTalk podcaster and East Hampton resident Neil DeGrasse Tyson, is that its true whether or not you believe it. Ameerr, right on!

Dr. Tysons new book, Astrophysics for People in a Hurry (Norton, $18.95),gives us as many reasons to believe as there are stars in the sky, which is to say, a near infinite number. Tysons grasp on this tricky subject is masterly; his ability to communicate his subject matter, second to none; his delivery and style, disarmingly simple and accessible; hes also funny in that dad-humor kind of way, as in Einstein was a badass. Sure, there will be instances of head scratching as you try to untangle the difference between a quark and photon, or to decipher just how small a trillionth of a second is. But we cant all be astrophysicists.

At times, through no fault of his own, Tyson makes us consider our insignificance in the 14,000,000,000-year history of our cosmos. Consider this doozy: Without the billion-and-one to a billion imbalance between matter and antimatter, all mass in the universe would have selfannihilated, leaving a cosmos full of photons and nothing else. Essentially, if conditions were only slightly different in the very first second after the big bang, there would be absolutely nothinga universe without galaxies, stars, earth, or even Dans Papers. Can you imagine!? As Tyson admits later, the utter scale of the universe and the topics he discusses in Astrophysics is a depressing thought to some, but a liberating thought to me. If youre susceptible to the former feeling, perhaps, after finishing Astrophysics, youll be feeling more like Dr. Tysonabuzz with all the possibilities of the universe.

Not to worry though. Were just as often made to celebrate the idea that despite all the odds against it, lifeyou, me, usnot only exists, but has thrived and evolved until the point that we can look up at the night sky and at least try to understand it. And as any science documentary watcher already knows, Tyson has a unique and infectious way of simplifying such mind numbingly complex issues and ideas in such fluid, easy-to-comprehend ways that youll be explaining the origins of the universe and dark energy to friends and family in no time. Astrophysics is no different.

So who might this slim volume be perfect for? Just about anyone. Curious to start understanding how the universe works? Go buy this book. Are you a science teacher looking for ways to better explain the most complex astrophysical phenomena to students or casual inquisitors? Go buy this book. Are you a budding young scientist whose curiosity is as boundless as the cosmos? Go buy this book. Does a loved one, despite your best efforts to convince them otherwise and scientific proof to the contrary, still believe humans and dinosaurs cohabited earth? Go buy them this book.

It may not be the perfect sunny-day beach read, though maybe it iswe dont know your life. At the very least, a good reader could make a serious dent in this relatively short book on a Jitney or LIRR ride to or from Manhattan. Better yet, get yourself a book light, head down to the nearest beach after sunset and dive in to Astrophysics.

Astrophysics for People in a Hurry is available at local bookstores.

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Book Review: 'Astrophysics for People in a Hurry' - Dan's Papers

LIGO’s Latest Black-Hole Merger Confirms Einstein, Challenges Astrophysics – Scientific American

Some three billion years ago, when Earth was a sprightly ocean world dotted with protocontinents and inhabited solely by single-celled organisms, a pair of black holes spiraled together and collided in a far-off region of the universe, leaving behind a single black hole some 50 times heavier than our sun. Emitting no light, the entire affair should have remained forever lost to the void.

Instead, the invisible violence of the pairs final moments and ultimate merging was so great that it shook the fabric of reality itself, sending gravitational wavesripples in spacetimepropagating outward at the speed of light. In the early morning hours of January 4, 2017, those waves washed over our modern Earth and into the most precise scientific instrument ever built, the Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO). There the waves shifted the positions of vacuum-insulated, laser-bathed mirrors by less than the radius of a single subatomic particle. Traveling at light-speed, the waves first perturbed LIGO mirrors set up in Hanford, Wash., before passing through a second set of mirrors in Livingston, La., some three milliseconds later. Synced together from each stations moving mirrors and converted to audible frequencies, the cosmos-quaking gravitational waves sounded like a single, soft chirp. Analyzing it, researchers are teasing out remarkable and otherwise-inaccessible details about the hidden lives of black holes. Announced Thursday by members of the LIGO team, the findings are described in Physical Review Letters.

As inconceivable as it may seem, tuning in to such chirps is now becoming routine. First predicted by Einstein more than a century ago as a consequence of his theory of general relativity, gravitational waves were long thought to be beyond observational reachif not entirely nonexistent. But the chirp from January 4, dubbed GW170104, is actually LIGOs third and farthest-reaching detection of gravitational waves, coming from somewhere about 3 billion light-years away. It follows earlier chirps from two other events detected separately in late 2015 that each occurred closer by, yet still more than a billion light-years distant.

Other cosmic phenomena such as supernovae in the Milky Way and colliding neutron stars in our galactic neighborhood should also produce detectable gravitational waves, each with their own accompanying revolutionary insights, but so far all three of LIGOs detections have been death-rattles from merging pairs of black holes in remote stretches of the universe.

For the time being, thousands of scientists around the world are making the most of LIGOs limited view and the projects three confirmed detections. Whereas the loudness of each chirp has clearly conveyed each events distance from us, LIGOs twin stations can at present only vaguely constrain their celestial sources, which may lie anywhere within huge swaths of the heavens containing thousands upon thousands of large galaxies. So thirsty are theorists for new insights into black holes and relativistic processes that, with each LIGO detection, observational astronomers have leapt into action to target those enormous patches of sky, hoping to see some afterglow or other emission of electromagnetic radiationeven though by definition the resulting larger black hole should emit no light.

Fortunately, even without light the mergers gravitational waves reveal much. LIGO team members have already used the billionlight-year intergalactic traverses of the first two chirps to look for signs of dispersion in the propagation of gravitational wavesa phenomenon analogous to how rays of light traveling through a prism disperse based on their wavelength to form rainbows. According to Einsteins theory of general relativity, gravitational waves should experience no dispersion at alland any deviation from that prediction would suggest Einsteins relativistic reckoning of the universe is somehow incorrect, potentially pointing the way to new breakthroughs in physics. Signs of any dispersion should have been obvious in LIGOs third event, GW170104, because its gravitational waves traveled across three billion light-years, rather than the one billion of LIGOs previous two events. But when researchers looked, they saw no gravitational rainbows. We made very careful measurement of that effect, said LIGO team member Bangalore Sathyaprakashof The Pennsylvania State University and Cardiff University. But we did not discover any dispersion, once again failing to prove that Einstein was wrong.

Using that same measurement, researchers also honed in on the mass of the graviton, the hypothetical particle that mediates the force of gravity. Basically we are testing general relativity in a new regime, says Laura Cadonati, a physicist at Georgia Institute of Technology and LIGOs deputy spokesperson. The fact that this event is twice as far as the previous two gives us a longer baseline to test the dispersion relation, and as a result we now have a limit on the mass of the graviton that is 30 percent tighter than the one we previously set. One could say we are putting general relativity to a tighter and tighter testit is still holding, but with more signals we may find something that does not quite agree.

Although LIGOs latest event may be a brick in the towering edifice of Einsteins general relativity, it is also restructuring the foundations of our understanding of black holes. Before LIGOs detections, astronomers only had definitive observations of two varieties of black holes: ones that form from stars that were thought to top out around 20 solar masses; and, at the cores of large galaxies, supermassive black holes of still-uncertain provenance containing millions or billions of times the mass of the sun. Both are thought to be important for understanding the formation and evolution of galaxies, and thus to some degree important for the formation and evolution of everything galaxies containincluding stars, planets and people. Most of the black holes in LIGOs mergers have been middleweights, being heavier than that 20solar mass limit but much lighter than the supermassive variety, raising questions about their origins and relationship to the two well-studied populations of black holes.

The prevailing explanation for LIGOs bulky black holes is that they form from very massive stars that are also quite pristine, composed almost entirely of hydrogen and helium with scarcely any heavier elements at all. Most stars of such immensity would have more heavy elements, causing them to lose much of their mass via high-speed winds whereas low metallicity stars would have weaker winds and keep more of their star stuff, ultimately ending their lives by collapsing to become overlarge stellar black holes.

Making LIGOs merging black hole pairs, one conventional theory goes, would then require the binary evolution of two massive, low-metallicity stars that form as a pair. If, for instance, the two stars are very close, over the courses of their lives they can swap gas from their atmospheres back and forth in a cyclic process that pulls their orbits even closer and eventually produces two tightly orbiting, supersize black holes. At the end of this process, the spins and orbits of both black holes would have become inextricably linked, so each black holes equator would be aligned with the plane of their shared orbit.

Think of black holes as being like tornadoes that drag stars and matter around them, Cadonati explains. Now think of two going around each other, and each one spinning clockwise or counterclockwise, aligned with the orbital motion. Two black holes with such an alignment would possess more rotational energy than an unaligned pair, and thus require ever-so-slightly more time to coalesce together in the final moments of their merger. The deepest mystery of GW170104, LIGOs latest discovery, is that the merger happened too quickly for both of its progenitor black holes to be so aligned; in terms of Cadonatis analogy, at least one of the orbiting tornadoes must have been paradoxically tilted near or on its side.

The most common explanation for black hole pairs with such spin misalignment is that they did not form from the binary evolution of isolated twin stars. Instead, each black hole must have formed independently, and somehow found its partner after millions or billions of years of wandering through the universe. Any eventual union through this dynamical formation channel would most likely take place in thick swarms of stars called globular clusters, says Fred Rasio, a physicist at Northwestern University who is not a member of the LIGO collaboration. Imagine throwing a thousand black holes into a mosh pit where they kick each other around like crazy, Rasio says. Their spins will be randomized. The dynamics dont care which way the holes are spinning, so when they are bound into a pair that merges, their spins have no correlation with how they orbit.

According to some theorists, the best explanation for GW170104s curious misalignment is that its black holes did not start out as stars at all. Even in dense globular clusters, these black holes would not form in sufficient density to find each other in the age of the universe, says Juan Garca-Bellido, a professor at the Autonomous University of Madrid who is not a member of the LIGO collaboration. Garca-Bellido is a leading proponent of the unorthodox idea that LIGOs abnormally heavy, oddly misaligned merging black holes are actually part of a putative population of primordial black holes. Rather than arising from stars, such exotic objects could have emerged in the first moments after the big bang, coalescing from particularly dense regions of the fiery plasmatic fog that then suffused the universe. If grouped in clusters, primordial black holes could also form merging pairs with misaligned spins.

There is, however, an additional wrinkle to ascribing primordial origins to some or all of LIGOs observed black holessomething that could be seen as either the theorys most alluring feature, or a nasty bug. Clusters of primordial black holes dense enough to produce LIGOs newfound population of merging ones, Garca-Bellido and others say, could also be a natural solution to the mystery of dark matterthe elusive and invisible 80 percent of the universes matter that astronomers see solely through its gravitational effects on glowing stars and gas in galaxies.

The idea would be that [the primordial black holes] would be concentrated in halos around the matter we can see, said Michael Landry, the head of LIGOs Hanford Observatory, summarizing the speculative concept in response to a question at a recent press conference. Its not impossible that what were seeing are primordial black holes that form the dark matter. On the other hand, Landry added, some teams of astronomers occasionally looking for halos of primordial black holes around the Milky Way have yet to find evidence they exist in sufficient numbers to account for the effects of dark matter. Whether black holes from the big bang explain dark matternot to mention LIGOs resultsis an open question, Landry said.

Whether born from binary evolution, dynamical pairing, the big bang or something else entirely, the true origins of LIGOs mysterious black hole mergers could soon be revealed. The collaborations current best guess is that somewhere between 12 and 213 such mergers occur each year in a cubic volume of space a bit over three billion light-years on a side. This suggests LIGOwhich is in the midst of upgrades to boost its sensitivity and planning for a new station in Indiacould eventually be detecting the chirps from black hole mergers at a rate of anywhere between once per day to once per week. Upgrades are also in progress for Virgo, a companion gravitational-wave observatory approaching LIGOs sensitivity. As early as this summer both projects will simultaneously monitor the sky to better localize the origins of any new celestial gravitational grumbles. Beyond LIGO and Virgo, additional observatories are likely to debut in coming years around the world, creating a globe-girdling network for finer-grained gravitational-wave searches. By the 2020s, the chirps will come so fast and furious, from so many merging pairs of black holes, their sounds could form a symphony.

Its not a single one or two black hole binaries by which we can distinguish between different models, Sathyaprakash said. Its only from a population of detections, which will give us distributions for spins and for masses. Thats where the differences between formation mechanisms will become clear. Very heavy, misaligned black hole pairs could prove to be very rare, strengthening the case that most mergers come from isolated systems of binary starsor they could prove common, suggesting denser, more dynamical origins. And if, Garca-Bellido says, any black hole in a LIGO merger proves to weigh less than our sun, this would be a smoking gun for primordial black holes, as such relatively minuscule black holes are thought impossible to form from stars.

Before our discovery, we didnt even know for sure that these [middleweight] black holes existed, Cadonati said at the press conference announcing GW170104. What we do know now is, first of all, they do exist, they may have played an important role in the early universe and were now starting to get a glimpse into how they behaved. This has really opened a new window on the universe, and were learning more about where were coming from. Thats the big excitement.

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LIGO's Latest Black-Hole Merger Confirms Einstein, Challenges Astrophysics - Scientific American

Mystery of Gravitational-Wave Astrophysics –"How Two Black Holes Can Come Together and Merge" – The Daily Galaxy (blog)

Astrophysicists at the University of Birmingham have made progress in understanding a key mystery of gravitational-wave astrophysics: how two black holes can come together and merge. Senior author Ilya Mandel added: "This work makes it possible to pursue a kind of 'palaeontology' for gravitational waves. A palaeontologist, who has never seen a living dinosaur, can figure out how the dinosaur looked and lived from its skeletal remains. In a similar way, we can analyse the mergers of black holes, and use these observations to figure out how those stars interacted during their brief but intense lives."

The first confirmed detection of gravitational waves occurred on September 14 2015 at 5.51am Eastern Daylight Time by both of the twin LIGO detectors, located in Livingston, Louisiana, and Hanford, Washington, USA. It confirmed a major prediction of Albert Einstein's 1915 general theory of relativity and opened an unprecedented new window onto the cosmos. However, we still do not know how such pairs of merging black holes form.

A new paper, published in Nature Communications, describes the results of an investigation into the formation of gravitational-wave sources with a newly developed toolkit named COMPAS (Compact Object Mergers: Population Astrophysics and Statistics).

In order for the black holes to merge within the age of the Universe by emitting gravitational waves, they must start out very close together by astronomical standards, no more than about a fifth of the distance between the Earth and the Sun. However, massive stars, which are the progenitors of the black holes that LIGO has observed, expand to be much larger than this in the course of their evolution.

The key challenge, then, is how to fit such large stars within a very small orbit. Several possible scenarios have been proposed to address this.

The Birmingham astrophysicists, joined by collaborator Professor Selma de Mink from the University of Amsterdam, have shown that all three observed events can be formed via the same formation channel: isolated binary evolution via a common-envelope phase.

In this channel, two massive progenitor stars start out at quite wide separations. The stars interact as they expand, engaging in several episodes of mass transfer. The latest of these is typically a common envelope - a very rapid, dynamically unstable mass transfer that envelops both stellar cores in a dense cloud of hydrogen gas. Ejecting this gas from the system takes energy away from the orbit. This brings the two stars sufficiently close together for gravitational-wave emission to be efficient, right at the time when they are small enough that such closeness will no longer put them into contact.

The whole process takes a few million years to form two black holes, with a possible subsequent delay of billions of years before the black holes merge and form a single black hole.

The simulations have also helped the team to understand the typical properties of the stars that can go on to form such pairs of merging black holes and the environments where this can happen. For example, the team concluded that a merger of two black holes with significantly unequal masses would be a strong indication that the stars formed almost entirely from hydrogen and helium, with other elements contributing fewer than 0.1% of stellar matter (for comparison, this fraction is about 2% in the Sun).

First author Simon Stevenson, a PhD student at the University of Birmingham, explained: "The beauty of COMPAS is that it allows us to combine all of our observations and start piecing together the puzzle of how these black holes merge, sending these ripples in spacetime that we were able to observe at LIGO."

The Daily Galaxy via University of Birmingham

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Mystery of Gravitational-Wave Astrophysics --"How Two Black Holes Can Come Together and Merge" - The Daily Galaxy (blog)

The tortoise: Blue Origins sees small steps as key to space business – Christian Science Monitor

March 8, 2017 A week after SpaceX founder Elon Musk stole headlines with his proposal to send two paying customers on a flight around the moon next year, another private space company came out with more modest news.

Blue Origin, founded by Amazon chief executive officer Jeff Bezos, has contracted with French telecom firm Eutelsat to send a communications satellite into orbit on its New Glenn rocket, scheduled for completion in 2020.

Since its founding in 2009, SpaceX has already carved out a niche in the satellite-launch market and resupplied the International Space Station. Meanwhile, Mr. Bezoss 16-year-old firm has only flown its New Shepard capsule and booster rocket to the edge of space.

But Blue Origin sports a tortoise on its coat of arms, and Mr. Bezos appears content to play that role to Mr. Musks hare. He says he's confident that small, incremental progress will help Blue Origin prosper in the long run.

I like to do things incrementally, Bezos remarked during Tuesdays Satellite 2017 Conference in Washington, The New York Times reports. His companys motto, gradatim ferociter, means Step by step, ferociously.

Eutelsat rewarded this approach in its decision to grant Blue Origin the contract. While the company has launched satellites with SpaceX in the past, Eutelsat's chief executive, Rodolphe Belmer, suggested that Blue Origin's slow and steady approach better aligns with that of his company.

Blue Origin has been forthcoming with Eutelsat on its strategy and convinced us they have the right mindset to compete in the launch service industry," Mr. Belmer said in a press release. "Their solid engineering approach ... corresponds to what we expect from our industrial partners.

While some have praised SpaceX's ambition, concerns are growing that, under Musks accelerated timelines, people working for the company might be run ragged by the demands, leading to human errors, as The Christian Science Monitor reported last week.

SpaceXhas repeatedly pushed back its target date for flying a crewed mission, raising eyebrows about its ability to make good on its promise to carry customers around the moon by next year.

"SpaceX has a great record of doing exactly what they say they're going to do but always several years later than they said they were going to do it, astrophysicist Jonathan McDowell told the Monitor last week.

Dr. McDowell, who teaches at the Harvard-Smithsonian Center for Astrophysics, made clear that he had full confidence that SpaceX would succeed in sending space tourists around the moon, but suggested 2020 might be a more likely deadline.

That would give Blue Origin more time to hone its technology and broaden its activities. In addition to satellite launches, the company plans to send deep-pocketed tourists into space aboard New Shepard, an activity that Bezos says will help the company further refine its technology and create a profitable business model for more ambitious space ventures.

"The tourism mission is very important, he said on Tuesday, CNBC reports. There are many historical cases where entertainment drives technologies that then become very practical for other things."

And while low-Earth orbit may not seem as exciting as the moon, Bezoss goals are no less ambitious than Musks.

The long-term vision is millions of people living and working in space, he said Tuesday, according to The New York Times.

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The tortoise: Blue Origins sees small steps as key to space business - Christian Science Monitor

The tortoise: Blue Origin sees small steps as key to space business – Christian Science Monitor

March 8, 2017 A week after SpaceX founder Elon Musk stole headlines with his proposal to send two paying customers on a flight around the moon next year, another private space company came out with more modest news.

Blue Origin, founded by Amazon chief executive officer Jeff Bezos, has contracted with French telecom firm Eutelsat to send a communications satellite into orbit on its New Glenn rocket, scheduled for completion in 2020.

Since its founding in 2009, SpaceX has already carved out a niche in the satellite-launch market and resupplied the International Space Station. Meanwhile, Mr. Bezoss 16-year-old firm has only flown its New Shepard capsule and booster rocket to the edge of space.

But Blue Origin sports a tortoise on its coat of arms, and Mr. Bezos appears content to play that role to Mr. Musks hare. He says he's confident that small, incremental progress will help Blue Origin prosper in the long run.

I like to do things incrementally, Bezos remarked during Tuesdays Satellite 2017 Conference in Washington, The New York Times reports. His companys motto, gradatim ferociter, means Step by step, ferociously.

Eutelsat rewarded this approach in its decision to grant Blue Origin the contract. While the company has launched satellites with SpaceX in the past, Eutelsat's chief executive, Rodolphe Belmer, suggested that Blue Origin's slow and steady approach better aligns with that of his company.

Blue Origin has been forthcoming with Eutelsat on its strategy and convinced us they have the right mindset to compete in the launch service industry," Mr. Belmer said in a press release. "Their solid engineering approach ... corresponds to what we expect from our industrial partners.

While some have praised SpaceX's ambition, concerns are growing that, under Musks accelerated timelines, people working for the company might be run ragged by the demands, leading to human errors, as The Christian Science Monitor reported last week.

SpaceXhas repeatedly pushed back its target date for flying a crewed mission, raising eyebrows about its ability to make good on its promise to carry customers around the moon by next year.

"SpaceX has a great record of doing exactly what they say they're going to do but always several years later than they said they were going to do it, astrophysicist Jonathan McDowell told the Monitor last week.

Dr. McDowell, who teaches at the Harvard-Smithsonian Center for Astrophysics, made clear that he had full confidence that SpaceX would succeed in sending space tourists around the moon, but suggested 2020 might be a more likely deadline.

That would give Blue Origin more time to hone its technology and broaden its activities. In addition to satellite launches, the company plans to send deep-pocketed tourists into space aboard New Shepard, an activity that Bezos says will help the company further refine its technology and create a profitable business model for more ambitious space ventures.

"The tourism mission is very important, he said on Tuesday, CNBC reports. There are many historical cases where entertainment drives technologies that then become very practical for other things."

And while low-Earth orbit may not seem as exciting as the moon, Bezoss goals are no less ambitious than Musks.

The long-term vision is millions of people living and working in space, he said Tuesday, according to The New York Times.

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"Fast Radio Bursts Could Be Powering Alien Probes" –Harvard … – The Daily Galaxy (blog)

"Fast radio bursts are exceedingly bright given their short duration and origin at great distances, and we haven't identified a possible natural source with any confidence," said theorist Avi Loeb of the Harvard-Smithsonian Center for Astrophysics. "An artificial origin is worth contemplating and checking."

As the name implies, fast radio bursts are millisecond-long flashes of radio emission. First discovered in 2007, fewer than two dozen have been detected by gigantic radio telescopes like the Parkes Observatory in Australia or the Arecibo Observatory in Puerto Rico. They are inferred to originate from distant galaxies, billions of light-years away.

Loeb and his co-author Manasvi Lingam (Harvard University) examined the feasibility of creating a radio transmitter strong enough for it to be detectable across such immense distances. They found that, if the transmitter were solar powered, the sunlight falling on an area of a planet twice the size of the Earth would be enough to generate the needed energy. Such a vast construction project is well beyond our technology, but within the realm of possibility according to the laws of physics.

Lingam and Loeb also considered whether such a transmitter would be viable from an engineering perspective, or whether the tremendous energies involved would melt any underlying structure. Again, they found that a water-cooled device twice the size of Earth could withstand the heat.

They then asked, why build such an instrument in the first place? They argue that the most plausible use of such power is driving interstellar light sails. The amount of power involved would be sufficient to push a payload of a million tons, or about 20 times the largest cruise ships on Earth.

"That's big enough to carry living passengers across interstellar or even intergalactic distances," added Lingam.

An artist's illustration of a light-sail powered by a radio beam (red) generated on the surface of a planet. The leakage from such beams as they sweep across the sky would appear as Fast Radio Bursts (FRBs), similar to the new population of sources that was discovered recently at cosmological distances.(M. Weiss/CfA)

To power a light sail, the transmitter would need to focus a beam on it continuously. Observers on Earth would see a brief flashbecause the sail and its host planet, star and galaxy are all moving relative to us. As a result, the beam sweeps across the sky and only points in our direction for a moment. Repeated appearances of the beam, which were observed but cannot be explained by cataclysmic astrophysical events, might provide important clues about its artificial origin.

Loeb admits that this work is speculative. When asked whether he really believes that any fast radio bursts are due to aliens, he replied, "Science isn't a matter of belief, it's a matter of evidence. Deciding what's likely ahead of time limits the possibilities. It's worth putting ideas out there and letting the data be the judge."

The paper reporting this work has been accepted for publication in the Astrophysical Journal Letters and is available online.

The Dily Galaxy via CfA

Image credit top of page, with thanks to Shutterstock/Jurik Peter

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"Fast Radio Bursts Could Be Powering Alien Probes" --Harvard ... - The Daily Galaxy (blog)

New survey finds ‘Peter Pan’ radio galaxies that may never grow up … – Science Daily


Science Daily
New survey finds 'Peter Pan' radio galaxies that may never grow up ...
Science Daily
A team of astronomers has doubled the number of known young, compact radio galaxies -- galaxies powered by newly energized black holes. The improved ...
Scientists Find 'Peter Pan' Radio Galaxies That Never Grow Up ...Science Times

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Women in science: celebrating the leading females in physics, chemistry and beyond – Wired.co.uk

DrAfter123/iStock

On International Women's Day, we celebrate the outstanding women in the WIRED world. In the first of our round-ups, we highlighted the females blazing a trail in business and culture. Now, we celebrate the women of science. Each of these inspirational females is speaking at this year's Starmus IV festival in Trondheim, Norway in June. On International Women's Day, WIRED highlights the females changing the world

Read more about the discoveries and contributions to neuroscience, physics, astrophysics, astronomy and biology made by female scientists across the world.

As Norwegian professor of neuroscience and founding director of the Center for Neural Computation, May is interested in how spatial location and spatial memory are computed in the brain. Her work includes the discovery of grid cells in the entorhinal cortex, which provides clues to a neural mechanism for the metric of spatial mapping. Moser was awarded the Nobel Prize in Physiology or Medicine 2014, together with long-term collaborator Edvard Moser and John OKeefe for their discoveries of cells that constitute a positioning system in the brain. Moser is also co-director of the Kavli Institute for Systems Neuroscience at the Norwegian University of Science and Technology in Trondheim.

Bailey is a British psychiatrist and academic who specialises in children's mental health. Since 2004 she has been professor of child mental health at the University of Central Lancashire. In 1993, Bailey appeared as an expert witness in the James Bulger murder trial. She established that one of Bulger's killers, Jon Venables, knew the difference between right and wrong: information that led to them being convicted of murder. In the 2002 Queen's Birthday Honours, Bailey was appointed an Officer of the Order of the British Empire (OBE) "for services to Youth Justice" and in the 2014 she was promoted to Dame Commander of the Order of the British Empire (DBE) "for services to psychiatry and for voluntary service to people with mental health conditions".

Professor Sara Seager is a planetary scientist and astrophysicist at the Massachusetts Institute of Technology. She has been a pioneer in the world of exoplanets and her groundbreaking research ranges from the detection of exoplanet atmospheres to innovative theories about life on other worlds and the development of novel space mission concepts. She is known for inventing the method used to study exoplanet atmospheres today. Dubbed an "astronomical Indiana Jones", Seager is on a quest for the discovery of a true Earth twin.

Hayhoe's work has resulted in more than 120 peer-reviewed publications that evaluate global climate model performance, develop and compare downscaling approaches, and quantify the impacts of climate change on cities, states, ecosystems, and sectors over the coming century. She has been named one of TIME's 100 Most Influential People and the Foreign Policy's 100 Leading Global Thinkers, as well as one of Politico's 50 thinkers, doers, and visionaries transforming American politics.

Born and raised in India, Natarajan received undergraduate degrees in Physics and Mathematics at MIT. Now a theoretical astrophysicist at Yale, Natarajan is recognised for her seminal contributions to the study of dark matter and the formation and growth of black holes.

Best known for her role in deciphering the molecular mechanisms of CRISPR-Cas9, Charpentier's lab discovered that Cas9 could be used to make cuts in any DNA sequence desired. Charpentier has been awarded several international prizes, awards, and acknowledgments including the Breakthrough Prize in Life Sciences, the Gruber Foundation International Prize in Genetics and the Leibniz Prize.

The director of the SETI Institute Carl Sagan Centre since August 2015, Cabrol is currently developing a new, multidisciplinary, roadmap to bridge astrobiology and the SETI search. She counts more than 470 peer-reviewed publications and proceedings of professional conferences.

Selected to the Nasa astronaut corps in 1996, Dr Magnus flew in space on the STS-112 shuttle mission in 2002, and on the final shuttle flight, STS-135, in 2011. In addition, she flew to the International Space Station on STS-126 in November 2008, served as flight engineer and science officer on Expedition 18, andreturned home on STS-119 after four and a half months on board. Following her assignment on Station, she served at NASA Headquarters in the Exploration Systems Mission Directorate. Her last duty at NASA, after STS-135, was as the deputy chief of the Astronaut Office.

Dr Magnus has received numerous awards, including the Nasa Space Flight Medal, the Nasa Distinguished Service Medal, the Nasa Exceptional Service Medal, and the 40 at 40 Award (given to former collegiate women athletes to recognize the impact of Title IX).

Starmus IV, hosted by NTNU, runs from June 18 to June 23 in Trondheim, Norway, tickets available from http://www.starmus.com.

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Indian women astronomers may be few, but they make us proud – DailyO

Birla planetariums are an attraction for children in many Indian cities. They literally open up the universe to young minds. This is what happened to a ten-year old girl from Daund in Maharashtra a few years ago on a visit to the Birla Planetarium in Kolkata. Today she is a budding astrophysicist engaged in cutting edge of astronomy hunting for exoplanets.

I was in Kolkata for marriage of a relative and thats when I saw a sky show for the first time. It was that moment I decided I wanted to be an astronomer, says Priyanka Chaturvedi, who just finished her PhD from theAhmedabad-based Physical Research Laboratory (PRL) run by the Indian Space Research Organisation (ISRO). She studied radial velocities of stars orbiting around exoplanets. Priyanka is now set to join the Tata Institute of Fundamental Research.

Most people who have travelled by train in Maharashtra know Daund as an important railway junction. Priyankas father is a railway employee. Since the town had few facilities for quality education, she moved to Pune to pursue BSc and then MSc at Fergusson College. We used to have long power cuts during summer in Daund, so we children used to watch stars. That interest has turned my profession now, she recalls. A visit to the Inter-University Centre for Astronomy and Astrophysics while she was in 12th standard also greatly influenced her to pursue astronomy.

Priyanka is among the small number of women engaged in astronomy and astrophysics research in India. A survey of women in astronomy in India done a couple of years ago showed that only a miniscule number of women are in faculty positions in research institutes engaged in astrophysics research. This is also a global trend with the exception of Italy which has a good number of women astronomers.

Still, women scientists have reached high positions in astrophysics institutes and contributed to astounding discoveries in recent times. GC Anupama is dean of Faculty of Sciences at the Indian Institute of Science in Bangalore. This institute runs Indias largest telescope Himalayan Chandra Telescope at Hanle in Ladakh. Data from this telescope was used in the recent discovery of "another world" or the new planetary system by NASA. She is also involved in other international mega science projects including the Thirty Meter Telescope.

Annapurni Subramaniam, also from IIA, is a senior scientist engaged in astronomical data collection from Ultra Violet Imaging Telescope currently working onboard Indias first astronomical satellite, Astrosat, launched in September 2015. Her research group recently reported how 6 billion old "vampire" stars prey on celestial bodies. Another leading astronomer is S Seetha, who heads the Space Science Programme Office at ISRO.

Yet astronomy is considered a tough option for women because observational astronomy involves working in nights at observatories which are usually located at far off locations. People are also not used to seeing women working in observatories. Visitors at Hanle used to be surprised finding a woman leading the observation team, recalled Anupama about her early experience.

Priyanka had to spend ten nights every month for observations at the Infrared Observatory of ISRO located at Mount Abu. I did not have much difficulty convincing my parents about this though they were little hesitant in the beginning, says Priyanka.

While the small number of women in astronomy is an issue, the Astronomical Society of India (ASI) is worried about overall shortage of professional astronomers in India which just 500 to of 700 of them. We need at least ten time this number given the fact that we are in the midst so many exciting mega science projects in which India is participating, says Sheo Kumar Pandey, president of ASI, which is holding its annual meeting in Jaipur currently. Hopefully more women will take up this stream of science and make many more exciting discoveries in future.

Meanwhile, Priyanaka says she plans to visit the Birla Planetarium in Jaipur taking time off from scientific deliberations at the ASI conference.

Also read -Why the world has always been a hard place for women scientists

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Indian women astronomers may be few, but they make us proud - DailyO

Iowa Newspaper Calls for Resignation of ‘Sizzler U’ Lawmaker – NBCNews.com

Iowa State Sen. Mark Chelgren, R-Ottumwa, at the Statehouse in Des Moines, Iowa on Feb. 8, 2017. Charlie Neibergall / AP, file

The Republican lawmaker, who supporters have dubbed "the Donald Trump of Iowa," got into hot water last week after

Ottumwa Courier publisher Wanda Moeller told NBC News this was the last straw for many in the rural town of 25,000 that Chelgren has represented since 2010.

"A lot of the public officials we spoke to over the weekend are just really upset by him," she said. "He's given the town a black eye. The first time he got elected it was just by 10 votes. The second time he won by 400. It's going to be an uphill battle for him if he tries to run again."

Chelgren, who did not immediately return a call for comment Monday, has denied inflating his resume and told NBC News he was not aware of the error on the GOP web site until a reporter asked him about it.

NBC began looking into Chelgren's education background after he proposed controversial

Chelgren claimed his own experiences with "liberal professors" prompted him to put forward a plan to impose a hiring freeze until the number of registered Republicans and Democrats on university faculties were within 10 percent of each other.

Confronted with the discrepancy, the GOP removed the Forbco reference from Chelgren's biography on the

At a rally on Saturday attended by about 60 people where he was introduced as "our own version of Donald Trump," Chelgren

Chelgren makes no mention of any associates degree on the amended GOP web site, which now just states he attended the University of California at Riverside "majoring in astro-physics, geo-physics and mathematics."

But Chelgren, who runs a wheelchair parts manufacturing firm called

A UCR spokesman has confirmed that Chelgren did attend the university, but just for one year and that he majored in physics and did not earned a degree.

"He did not complete his studies here," spokesman John Warren told NBC News last week, adding that he was enrolled for just one year from 1992 to 1993.

On the Frog Legs site, Chelgren also claimed to have worked as manager and auditor for Forbco Management in Anaheim, an apparent reference to the Sizzler operation.

Sanchez, Rebecca (206453029)

Sizzler spokeswoman Janet Ritter told NBC she can confirm Chelgren was employed by Sizzler back in the early 90s.

"Sizzler does do internal training and development," she said. "The certificate the Iowa senator claims to have would have qualified him to manage a Sizzler."

Chelgren also declares on his company website that he worked as a "Geo-Physist for GeoSoils in Temecula," which is a city in Riverside County, California.

The Iowa pol did not state on his company site when he worked for GeoSoils and the word "geophysicist" is misspelled.

Responding to a request from NBC News, Debbie Beach of GEO Soils Inc. said she would try to confirm that Chelgren had indeed employed by them. She also said they don't have an office in Temecula.

"It's in Murrieta, which is the town next door," said Beach.

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Astronomer Ruth Murray-Clay appointed to chair in theoretical astrophysics – UC Santa Cruz (press release)

Astrophysicist Ruth Murray-Clay gave a brief overview of her research on planetary systems at the investiture ceremony. (Photos by Steve Kurtz)

James Gunderson described how he and his wife Valerie Boom were inspired to establish the E. K. Gunderson Family Chair in Theoretical Astrophysics.

Ruth Murray-Clay, professor of astronomy and astrophysics at UC Santa Cruz, was honored as the inaugural holder of the E. K. Gunderson Family Chair in Theoretical Astrophysics at an investiture ceremony on Wednesday, March 1, at the University Center.

The chair was established in 2016 with a $160,000 gift from James L. Gunderson and Valerie J. Boom to support recruitment of a faculty member in astronomy and astrophysics. The chair honors the work of Gunderson's father, a psychologist whose work on human adaptation to confined and extreme conditions was used by NASA in understanding the implications of space travel.

Murray-Clay studies the formation and evolution of the solar system and of planetary systems around other stars. She explores a broad range of physical processes that contribute to the ultimate structure of planetary systems, including the evolution of the protoplanetary disk, planet formation, gravitational dynamics, and the evolution of atmospheres. She also studies objects in the outer reaches of our solar system for clues to its dynamical evolution.

"I am excited and honored to be here and to be the recipient of this chair," said Murray-Clay, who joined the UCSC astronomy faculty in 2016. She received her bachelor's degree in physics and astronomy at Harvard University and her master's and Ph.D. degrees in astrophysics at UC Berkeley. In 2015, Murray-Clay won the Helen B. Warner Prize for Astronomy, which recognizes the exceptional contributions of astronomers under the age of 36.

Increasing support for faculty chairs is a priority of the Campaign for UC Santa Cruz, which has raised $311 million for the campus.The Gunderson Family Chair in Theoretical Astrophysics is a four-year term chair (not an endowed chair) specially designed to augment the startup funding the campus provides for new faculty. Paul Koch, dean of physical and biological sciences, said such chairs provide important support for a new faculty member's research and graduate students. "The support from these chairs allows us to be competitive and attract the best faculty," he said.

The Campaign for UC Santa Cruz supports excellence across the university through increased private investment in the people and ideas shaping the future. It is bringing critical new resources to the student experience, excellence in research, and the campus commitment to environmental and social justice.

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Astronomer Ruth Murray-Clay appointed to chair in theoretical astrophysics - UC Santa Cruz (press release)

Supernova clues from neutrinos – Nature.com

Neutrinos detected by Earth-based observatories could one day help to reveal the sequence of events that occur in supernovae.

When a white-dwarf star becomes too massive to support itself, the internal pressure is thought to trigger a runaway thermonuclear reaction followed by an explosion known as a Type Ia supernova but the events involved in the explosion are unknown. Warren Wright at North Carolina State University in Raleigh and his colleagues simulated a supernova and calculated the number of neutrinos it would generate, and the timing of their release, if the star's gravity initially limited the explosion, and the nuclear reaction spread across the star's entire surface before the star exploded.

This would create two distinct neutrino bursts that would be much fainter than the single burst that would be made by a faster explosion, which the team calculated in a previous study published last year. Over time, neutrino observatories searching for supernovae in our Galaxy should be able to use these predictions to tell whether either scenario is accurate, the authors say.

Phys. Rev. D 95, 043006 (2017)

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Supernova clues from neutrinos - Nature.com

What Has Astrophysics Done For You Lately? – Big Think

Alex Filippenko: One can wonder why does astronomy, or any sort of abstract pure research for that matter, make any difference to us to the typical person in the world? Well first of all thinking about the universe and figuring out how things work is something that of all animals only humans can do, only we have the intellect, the curiosity, the opposable thumb with which to build machines to explore nature. So some of us should do it. Second of all these kinds of discoveries, discoveries about the cosmos excite kids. I like to say that astronomy is the gateway science. It gets kids interested in science and technology because they hear about all these amazing discoveries. I myself as a kid was thrilled by the lunar landings of the Apollo mission. Now most kids won't go on into astrophysics, but what they'll do is they'll study science and technology and they'll go into fields that are more immediately useful to society, such as applied physics and engineering and computer science and medical physics. But the bug that bites them is often astronomy.

And finally you never know what practical spinoffs there might be and let me give you a few examples. A century ago when quantum physicists such as Einstein and Bohr and Heisenberg and Schrodinger were developing quantum physics they had not the slightest practical application in mind. They didn't want to make a better toaster or a better bicycle or whatever. They wanted to understand the nature of light and why atoms exist, why atoms are stable, and other such questions of that sort that seem incredibly far removed from our everyday lives. Well fast forward a century, you could not imagine today's high-tech world without an understanding of the microphysics, the quantum world. Look at the silicon revolution for example. Look at lasers. Look at nearly everything it all stems from quantum physics. Who would've thought that a century ago?

Another even perhaps more abstract idea is Einstein's general theory of relativity, the theory that the presence of mass or energy curves or warps the shape of space and of time around it. So, for example, our sun forms a dimple in space and earth moves along its natural path through that dimple. So too earth forms a dimple and the moon moves along its natural path through that warped space. That's what gravity is. Newton had a formula for gravitational attraction but he didn't know what it was and Einstein came up with a theory. Well you might say who cares as long as gravity works what do we care what the exact mechanism is? Well, it turns out that Einstein's theory makes predictions that are in subtle ways different from Newton's predictions. And for things like the global positioning system, GPS, you have to take the effects of general relativity into account. The clocks in the satellites up in space, these satellites communicate with your device in your car, they run at a slightly faster speed than the clocks here on earth. And if that difference in the rate of passage of time had not been taken into account by the physicist and engineers who designed and built the GPS system, GPS wouldn't work. So here's something of incredible military and commercial value that simply would not work if we didn't understand gravity in a fundamental way according to Einstein, this idea of curved space time.

So again, who would've thought that a century ago when Einstein was developing the general theory of relativity that it would have this incredible practical application? Sure we might never get close to a black hole, which is an extreme prediction of general relativity, but it doesn't matter. The theory was developed, it's beautiful, it excites kids and it even has practical applications. So with much of astronomy we don't know what the spinoffs will be, but we do know that as humans we can accomplish these goals and we can also excite kids into pursuing areas of science and technology. And that in my opinion is really good.

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Astronomy Enthusiasts Over The Moon After Exoplanet Discovery – Harvard Crimson

The discovery of seven Earth-sized planetsat least three of which may be able to support lifeorbiting a nearby star has thrilled Harvard astronomy scholars and enthusiasts.

A team of astronomers published findings in the journal Nature Feb. 22 that the seven planets40 light-years from Earthmay be prime candidates for extraterrestrial life forms. According to researchers, last weeks discovery is the first in which multiple Earth-sized planets were found orbiting the same star.

For Andrew W. Mayo 17, vice president of the Student Astronomers at Harvard-Radcliffe and a joint Physics and Astrophysics concentrator, the discovery brought pure excitement.

Mayo said last weeks findings mark the largest discovery in the exoplanet field since NASAs 2009 Kepler Space Mission, which found other Earth-sized planets much further away from Earth than Trappist-1, which the seven planets orbit. Because researchers found three planets in the habitable zone, he said, it was a much more interesting discovery than those made in the past.

David Charbonneau, an astronomy professor, said that the Kepler Mission revealed that small, rocky planets often orbit small stars. After the Kepler Mission concluded, Charbonneau and an astronomy graduate student conducted a follow-up study that found that about one in four stars have planets roughly the size and temperature of Earth. Charbonneau said, however, that the stars studied in the Kepler Mission were very far away.

Trappist-1s solar system, by contrast, is only 40 light-years away, which is relatively close for astronomical research and accessible via telescope. Charbonneau said that the relative closeness of the newly discovered planets means that astronomers may be able to study their properties and look for life.

Andrew M. Vanderburg, a graduate student studying planetary systems at the Harvard-Smithsonian Center for Astrophysics, said he thinks the biggest thing these planets show is that were on the right track.

Mayo said he is excited to see further research on the Trappist-1 discovery.

Everyone who is involved in astronomy on campus is very intrigued by the discovery, and beyond that, I think were all excited to see what people find in the coming years, Mayo said. Theres a lot of follow-up to be done.

Vanderburg added that similar and follow-up projects are already happening at Harvard. Professor Charbonneaus MEarth project, for example, which also looks for exoplanets orbiting small stars, is similar to the project that found the Trappist-1 planets. The MEarth project specifically examines stars close to Earth and looks for rocky planets with the potential to sustain life.

According to Vanderburg, the Giant Magellan Telescope will be able to detect biosignatures, or certain molecules like methane, carbon, and oxygen which signal the presence of life. This and the other telescope projects will allow scientists to analyze the seven recently discovered planets and determine whether or not they contain life relatively soon, Vanderburg said.

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Astronomy Enthusiasts Over The Moon After Exoplanet Discovery - Harvard Crimson

Neural networks promise sharpest ever images – Science Daily

Neural networks promise sharpest ever images
Science Daily
But, when techniques such as machine learning emerge, astrophysics also provides a great test bed for tackling a fundamental computational question - how do we integrate and take advantage of the knowledge that humans have accumulated over ...

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Q&A with astrophysics professor Gerald Cecil about SpaceX’s rocket launch – The Daily Tar Heel

Luke Bollinger | Published 02/20/17 9:13pm

UNC astrophysics professor Gerald Cecil

SpaceX launched and landed a Falcon rocket Sunday from a historic NASA launch pad at Kennedy Space Centerin Florida. This mission was a step forward for Elon Musk's company they plan to send a rotation ofpeople to the International Space Station and eventually to Mars. Daily Tar Heel Staff Writer Luke Bollinger spoke with Gerald Cecil, a UNC astrophysics professor, to discuss the privatization of the space industry and the future of space exploration.

The Daily Tar Heel:With this new element of a competitive space industry within the U.S., do you think this is good for research and further development?

Gerald Cecil: Yeah, it is good. What it does is lower the entry point for payloads into space. If you can get the costs of flying one of these things down to a few million bucks, then any university level (principal investigator) whos interested and wants to do something in zero G can fly on a Falcon up to a Bigelow-inflated space station and sit up there for years. At the moment, the entry point is more involved because you go through NASA. There are multiple runs before you fly your payload on the space station. With a privately available space station and private launching, cost price should be much lower.

DTH: What is NASAs role right now? Obviously they are still involved, but in what capacity?

GC: They run the space station. They run all of the science operations on the space station. Theyre responsible for contracting the rocket boosters. They dont provide their own booster; they contract them from SpaceX and Orbital ATK and a couple of other companies. Eventually, the idea would be that NASA would give up all of the low earth orbit stuff, including the space station, and focus on more distant destinations. I think we have to get to the point where Bigelow demonstrates that they can inflate one of their big space station modules and stick a couple together. All they have to do is stick two together and they get almost the same volume as the International Space Station.

DTH: How does a companys motivation to make a profit and make money for its shareholders affect the type of research or product design that they do?

GC: The most successful space products that have come out so far have been in pharmaceuticals. There was a flurry of all that in the '80s and '90s, when the shuttle started flying. I dont really think theres been any substantial advances since the space station got operational. Most of the programs you hear about are the NASA programs testing limited technologies potentially available for long-duration space flight to Mars and so on.

DTH: One of the big conversations you hear when discussing privatizing space exploration is space tourism. Could this possibly be a big funding factor? How would space tourism factor in the process of research and development?

GC: Bigelows modules are designed to be outfitted in some sort of configurations such as luxury, zero-G accommodation. If SpaceX demonstrates that all people have to do is endure a few gravities for eight minutes and half an hour down, then money is really the only issue. If you can crash the cost of access to space to 20 or 30,000 bucks, youre looking at people who would normally take a cruise somewhere in a luxury yacht or whatever now considering going up to space.What they do up there is another matter. After youve had your sky-high club experience, you can look out the window. Theres got to be some level of interaction up there that cant be done on the ground. Pretty much, its just the view at this point. If Bigelow is able to inflate something big enough, then you can imagine people floating around in giant volumes, in football stadium volumes. That could be kind of amusing, flying around and everything. But, theres not much discussion of that at the moment.

DTH: Juxtaposing the leadership of space exploration such as someone like Elon Musk and a government organization what are some of the differences that youve seen?

GC: Musk has a strategy because he has an end goal, which is to get to Mars, to die on Mars. Hopefully, later rather than sooner. The U.S. has no strategy in space beyond the one its executing now, which is a jobs program in a few congressional districts. The booster theyre building now is going to be so expensive. It will fly a few times at most before it will have to be mothballed because it will be vastly overpriced compared to the alternatives. Musks focus is to get the price as low as possible because he knows how many missions he will have to launch into Earth orbit to prepare to go to Mars.

@BollingerLuke

state@dailytarheel.com

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