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Chinese mountain observatory to probe cosmic-ray origins

Astronomy News - 16 March 2017 - 9:14am

Chinese mountain observatory to probe cosmic-ray origins

Nature 543, 7645 (2017). http://www.nature.com/doifinder/10.1038/543300a

Author: David Cyranoski

The massive project will intercept γ-ray showers in an unexplored energy band.

Astrophysics: Distant galaxies lack dark matter

Astronomy News - 16 March 2017 - 9:14am

Astrophysics: Distant galaxies lack dark matter

Nature 543, 7645 (2017). doi:10.1038/543318a

Authors: Mark Swinbank

The masses of nearby spiral galaxies are dominated by invisible 'dark matter'. Surprisingly, galaxies in the distant Universe seem to contain comparatively little of it. See Letter p.397

Dark matter took its time to wrap around early galaxies

Astronomy News - 16 March 2017 - 9:12am

Large spiral galaxies today rotate more quickly than they should, but was it always that way? New maps of ancient galaxies suggest a dark secret

NASA Selects Investigations for First Mission to Encounter the Sun

Astronomy News - 16 March 2017 - 9:11am
Portal origin URL: NASA Selects Investigations for First Mission to Encounter the SunPortal origin nid: 398556Published: Wednesday, March 15, 2017 - 14:33Featured (stick to top of list): noPortal text teaser: WASHINGTON - NASA has begun development of a mission to visit and study the sun closer than ever before. The unprecedented project, named Solar Probe Plus, is slated to launch no later than 2018. The small car-sized spacecraft will plunge directly into the sun's atmosphere approximately four million miles from our star's surface. It will explore a region no other spacecraft ever has encountered. NASA has selected five science investigations that will unlock the sun's biggest mysteries. "The experiments selected for Solar Probe Plus are specifically designed to solve two key questions of solar physics - why is the sun's outer atmosphere so much hotter than the sun's visible surface and what propels the solar wind that affects Earth and our solar system? " said Dick Fisher, director of NASA's Heliophysics Division in Washington. "We've been struggling with these questions for decades and this mission should finally provide those answers." As the spacecraft approaches the sun, its revolutionary carbon-composite heat shield must withstand temperatures exceeding 2550 degrees Fahrenheit and blasts of intense radiation. The spacecraft will have an up close and personal view of the sun enabling scientists to better understand, characterize and forecast the radiation environment for future space explorers. NASA invited researchers in 2009 to submit science proposals. Thirteen were reviewed by a panel of NASA and outside scientists. The total dollar amount for the five selected investigations is approximately $180 million for preliminary analysis, design, development and tests. The selected proposals are: - Solar Wind Electrons Alphas and Protons Investigation: principal investigator, Justin C. Kasper, Smithsonian Astrophysical Observatory in Cambridge, Mass. This investigation will specifically count the most abundant particles in the solar wind - electrons, protons and helium ions - and measure their properties. The investigation also is designed to catch some of the particles for direct analysis. - Wide-field Imager: principal investigator, Russell Howard, Naval Research Laboratory in Washington. This telescope will make 3-D images of the sun's corona, or atmosphere. The experiment will also provide 3-D images of the solar wind and shocks as they approach and pass the spacecraft. This investigation complements instruments on the spacecraft providing direct measurements by imaging the plasma the other instruments sample. - Fields Experiment: principal investigator, Stuart Bale, University of California Space Sciences Laboratory in Berkeley, Calif. This investigation will make direct measurements of electric and magnetic fields, radio emissions, and shock waves that course through the sun's atmospheric plasma. The experiment also serves as a giant dust detector, registering voltage signatures when specks of space dust hit the spacecraft's antenna. - Integrated Science Investigation of the Sun: principal investigator, David McComas of the Southwest Research Institute in San Antonio. This investigation consists of two instruments that will monitor electrons, protons and ions that are accelerated to high energies in the sun's atmosphere. - Heliospheric Origins with Solar Probe Plus: principal investigator, Marco Velli of NASA's Jet Propulsion Laboratory in Pasadena, Calif. Velli is the mission's observatory scientist, responsible for serving as a senior scientist on the science working group. He will provide an independent assessment of scientific performance and act as a community advocate for the mission. "This project allows humanity's ingenuity to go where no spacecraft has ever gone before," said Lika Guhathakurta, Solar Probe Plus program scientist at NASA Headquarters, in Washington. "For the very first time, we'll be able to touch, taste and smell our sun." The Solar Probe Plus mission is part of NASA's Living with a Star Program. The program is designed to understand aspects of the sun and Earth's space environment that affect life and society. The program is managed by NASA'S Goddard Space Flight Center in Greenbelt, Md., with oversight from NASA's Science Mission Directorate's Heliophysics Division. The Johns Hopkins University Applied Physics Laboratory in Laurel, Md., is responsible for formulating, implementing and operating the Solar Probe Mission. For more information about the Solar Probe Plus mission, visit:   http://solarprobe.gsfc.nasa.gov/   For more information about the Living with a Star Program, visit: http://science.nasa.gov/about-us/smd-programs/living-with-a-star/   - end - text-only version of this release NASA press releases and other information are available automatically by sending a blank e-mail message to hqnews-subscribe@mediaservices.nasa.gov. To unsubscribe from this mailing list, send a blank e-mail message to hqnews-unsubscribe@mediaservices.nasa.gov. Back to NASA Newsroom | Back to NASA Homepage Portal image: NASA logoScience Categories: Sun

Dark Matter Less Influential in Galaxies in Early Universe

Astronomy News - 16 March 2017 - 9:10am
New observations indicate that massive, star-forming galaxies during the peak epoch of galaxy formation, 10 billion years ago, were dominated by baryonic or “normal” matter. This is in stark contrast to present-day galaxies, where the effects of mysterious dark matter seem to be much greater. This surprising result was obtained using ESO’s Very Large Telescope and suggests that dark matter was less influential in the early Universe than it is today. The research is presented in four papers, one of which will be published in the journal Nature this week.

Asteroid clay is a better space radiation shield than aluminium

Astronomy News - 15 March 2017 - 9:31am

Cosmic radiation poses one of the biggest health risks for astronauts on long space missions, but clay extracted from space rocks could protect them

Celebrating 10 years of European research excellence

Astronomy News - 14 March 2017 - 9:06am

When European government representatives met in Lisbon in the year 2000, and expressed an aspiration that Europe should become the world's leading knowledge economy by 2010, they agreed on the need to create a body to “fund and co-ordinate basic research at European level”.

This was the impetus underlying the creation, in 2007, of the European Research Council (ERC).

Ten years after its foundation, the ERC has become a European success story. It has supported some 6,500 projects through its prestigious grants, and has become a unique model for the fostering and funding of innovative academic research.

To mark the anniversary, events are being held across Europe during ERC Week, running from 13-19 March. At the University of Cambridge, various recipients of ERC grants will be sharing their findings with a wide audience in talks scheduled as part of the Cambridge Science Festival.

The McDonald Institute for Archaeological Research will be joining in ERC Week celebrations by hosting a conference on Thursday, 16 March.

On the same day, a reception for Cambridge recipients of ERC grants, attended by ERC president Prof. Jean-Pierre Bourguignon, will be held at the Fitzwilliam Museum, which is currently showing the ERC-supported exhibition, “Madonnas and Miracles: The Holy Home in Renaissance Italy”.

The ERC supports outstanding researchers in all fields of science and scholarship. It awards three types of research awards (Starter, Consolidator, Advanced) through a competitive, peer-reviewed process that rewards excellence. Its focus on “frontier research” allows academics to develop innovative and far-reaching projects over five-year periods.

The United Kingdom has been the largest recipient of ERC awards –between 2007 and 2015, it received 24% of all ERC funding.

To date, the ERC has supported 1524 projects by UK-based academics. Researchers at the University of Cambridge have won 218 of those grants, in fields ranging from Astrology to Zoology.

“What is special about an ERC grant?”, asks Dr Marta Mirazón Lahr, who was awarded an ERC Advanced Investigator Award for her project “IN-AFRICA”, which examines the evolution of modern humans in East Africa.

“An obvious side is that it’s a lot of money. But I think it’s more than just the money. Because it’s five years, the ERC grant allows you to get a group and build a real community around the project. It also allows you to explore things in greater depth.”

An ERC grant allowed Dr Debora Sijacki, at the Institute of Astronomy, to attract “a really competitive and international team, which otherwise would have been almost impossible to get.”

Being funded for a five-year period, she adds, “gives you time to expand and really tackle some of the major problems in astrophysics, rather than doing incremental research.”

It also allowed her access to facilities: “In my case, it was access to world-leading supercomputers. And without the ERC grant this would have been difficult.”

“Real progress in research is made when researchers can tackle big important questions," says Prof David Baulcombe, of the Department of Plant Sciences, the recipient of two ERC grants. "The ERC programme invites researchers to submit ambitious, blue-skies, imaginative proposals. There aren’t many others sources of funding that allow one to do that sort a thing.”

Dr Christos Lynteris, of the Centre for Research in the Arts, Humanities and Social Sciences (CRASSH), is the recipient of an ERC Starting Grant for his project “Visual representations of the third plague pandemic.

“An ERC is a unique opportunity," he says: “it fosters interdisciplinary work. It also fosters analytical tools and the creation of new methods.”

“It offers a great opportunity to work with other people, over a period of 5 years, which is something very unusual, and with quite a liberal framework, so you are able to change and shift your questions, to reformulate them. For me, it means freedom, above everything.”

For Prof. Ottoline Leyser, Director of the Sainsbury Laboratory, it is the “ERC ethos” and its “emphasis on taking things in new directions” that has made all the difference.

The ERC values an innovative, risk-taking approach “in a way that conventional grant-funding schemes don’t –they usually want to see that slow build rather than the risky step into the unknown.”

Prof. Simon Goldhill, Director of CRASSH, was awarded an ERC Advanced Investigator Award for his project “Bible and Antiquity in 19th Century Culture”. It has given him “the unique opportunity to do a genuinely interdisciplinary collaborative project with the time and space it takes to make such interdisciplinarity work.”

“Most importantly,” he adds, “the financial model offered by this sort of project enables us to do work that is 15 or 20 years ahead of the rest of the world, and Britain and Europe are all the stronger for it.”

The sentiment is echoed by Prof. Ruth Cameron, of the Department of Materials Science and Metallurgy. The impact of an ERC grant for her project “3D Engineered Environments for Regenerative Medicine” has, she says, “exceeded expectations”.

So what has the ERC ever done for us? Quite a lot, say Cambridge academics, as they mark the 10th anniversary of Europe’s premier research-funding body

The financial model offered by this sort of project enables us to do work that is 15 or 20 years ahead of the rest of the world. Britain and Europe are all the stronger for it.Prof. Simon Goldhill, CRASSH


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TRAPPIST-1 worlds are close enough for life to hop between them

Astronomy News - 14 March 2017 - 9:04am

Some think life came to Earth from Mars on a meteorite. If this sort of thing can happen, it’s 1000 times more likely on TRAPPIST-1’s three habitable worlds

Enceladus' south pole is warm under the frost

Astronomy News - 14 March 2017 - 9:01am

Over the past decade, the international Cassini mission has revealed intense activity at the southern pole of Saturn's icy moon, Enceladus, with warm fractures venting water-rich jets that hint at an underground sea. A new study, based on microwave observations of this region, shows that the moon is warmer than expected just a few metres below its icy surface. This suggests that heat is produced over a broad area in this polar region and transported under the crust, and that Enceladus' reservoir of liquid water might be lurking only a few kilometres beneath.

Discovery of tiny moon completes the set for worlds past Neptune

Astronomy News - 10 March 2017 - 9:33am

The third-largest dwarf planet has a small satellite, meaning every object bigger than 1000 kilometres across in the outer solar system has a moon of its own

Planetary science: Volcano gas makes worlds habitable

Astronomy News - 9 March 2017 - 9:55am

Planetary science: Volcano gas makes worlds habitable

Nature 543, 7644 (2017). doi:10.1038/543152c

Gases from erupting volcanoes could make planets beyond the Solar System warmer and hospitable to life, even if the planet is relatively distant from its host star.Ramses Ramirez and Lisa Kaltenegger of Cornell University in Ithaca, New York, used a climate model to study

Tribute: Vera Rubin and the dark matter problem

Astronomy News - 9 March 2017 - 9:55am

Tribute: Vera Rubin and the dark matter problem

Nature 543, 7644 (2017). doi:10.1038/543179d

Author: Albert Bosma

In my view, Neta Bahcall's obituary of Vera Rubin oversimplifies the dark matter problem (Nature542, 32;10.1038/542032a2017). Many diverse observations have contributed to the current picture, and the unknown nature of dark matter shows that this is still far

Fuzzy pulsars orbiting black holes could unmask quantum gravity

Astronomy News - 9 March 2017 - 9:54am

Random changes in the radio beam of a pulsar orbiting a black hole could be telltale quantum effects, giving us a way to test theories of quantum gravity

Ancient Stardust Sheds Light on the First Stars

Astronomy News - 9 March 2017 - 9:51am
Astronomers have used ALMA to detect a huge mass of glowing stardust in a galaxy seen when the Universe was only four percent of its present age. This galaxy was observed shortly after its formation and is the most distant galaxy in which dust has been detected. This observation is also the most distant detection of oxygen in the Universe. These new results provide brand-new insights into the birth and explosive deaths of the very first stars.

Gravitational waves pioneer Ronald Drever dies

Astronomy News - 9 March 2017 - 9:44am

Scottish physicist Ronald Drever, one of the architects behind the discovery of gravitational waves, has died at the age of 85.

Oldest, biggest black holes may have come from enormous stars

Astronomy News - 8 March 2017 - 9:13am

Big black holes from just after the big bang couldn't have formed the way modern ones do - but they could come from the collapse of the largest stars ever

Moon’s hidden craters detected by gravity mapper

Astronomy News - 7 March 2017 - 9:15am

Astronomers have long suspected the existence of lunar craters filled in by ancient lava flows. A new approach could help us find all such impacts

The response of relativistic outflowing gas to the inner accretion disk of a black hole

Astronomy News - 2 March 2017 - 9:17am

The response of relativistic outflowing gas to the inner accretion disk of a black hole

Nature 543, 7643 (2017). doi:10.1038/nature21385

Authors: Michael L. Parker, Ciro Pinto, Andrew C. Fabian, Anne Lohfink, Douglas J. K. Buisson, William N. Alston, Erin Kara, Edward M. Cackett, Chia-Ying Chiang, Thomas Dauser, Barbara De Marco, Luigi C. Gallo, Javier Garcia, Fiona A. Harrison, Ashley L. King, Matthew J. Middleton, Jon M. Miller, Giovanni Miniutti, Christopher S. Reynolds, Phil Uttley, Ranjan Vasudevan, Dominic J. Walton, Daniel R. Wilkins & Abderahmen Zoghbi

The brightness of an active galactic nucleus is set by the gas falling onto it from the galaxy, and the gas infall rate is regulated by the brightness of the active galactic nucleus; this feedback loop is the process by which supermassive black holes in the centres of galaxies may moderate the growth of their hosts. Gas outflows (in the form of disk winds) release huge quantities of energy into the interstellar medium, potentially clearing the surrounding gas. The most extreme (in terms of speed and energy) of these—the ultrafast outflows—are the subset of X-ray-detected outflows with velocities higher than 10,000 kilometres per second, believed to originate in relativistic (that is, near the speed of light) disk winds a few hundred gravitational radii from the black hole. The absorption features produced by these outflows are variable, but no clear link has been found between the behaviour of the X-ray continuum and the velocity or optical depth of the outflows, owing to the long timescales of quasar variability. Here we report the observation of multiple absorption lines from an extreme ultrafast gas flow in the X-ray spectrum of the active galactic nucleus IRAS 13224−3809, at 0.236 ± 0.006 times the speed of light (71,000 kilometres per second), where the absorption is strongly anti-correlated with the emission of X-rays from the inner regions of the accretion disk. If the gas flow is identified as a genuine outflow then it is in the fastest five per cent of such winds, and its variability is hundreds of times faster than in other variable winds, allowing us to observe in hours what would take months in a quasar. We find X-ray spectral signatures of the wind simultaneously in both low- and high-energy detectors, suggesting a single ionized outflow, linking the low- and high-energy absorption lines. That this disk wind is responding to the emission from the inner accretion disk demonstrates a connection between accretion processes occurring on very different scales: the X-ray emission from within a few gravitational radii of the black hole ionizing the disk wind hundreds of gravitational radii further away as the X-ray flux rises.

Astrophysics: Supernova clues from neutrinos

Astronomy News - 2 March 2017 - 9:16am

Astrophysics: Supernova clues from neutrinos

Nature 543, 7643 (2017). doi:10.1038/543008b

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 —

Rapid changes point to origin of ultra-fast black hole winds

Astronomy News - 2 March 2017 - 9:15am

Outflowing gas is a common features of the supermassive black holes that reside at the centre of large galaxies. Often millions of times more massive than the Sun, these black holes feed off the surrounding gas that swirls around them. Space telescopes observe this as a bright light from the innermost part of the disc around the black hole.

Occasionally the black holes consume too much gas and release an ultra-fast wind. These winds are an important characteristic to study because they could have a strong influence on regulating the growth of the host galaxy by clearing the surrounding gas away and therefore suppressing the birth of stars.

Using ESA’s XMM-Newton and NASA’s NuStar telescopes, scientists have now made the most detailed observation yet of such an outflow. The winds recorded from the black hole reach 71,000 km/s – a quarter of the speed of light – putting it in the top 5% of fastest known black hole winds.

XMM-Newton focused on the black hole for 17 consecutive days, revealing the extremely variable nature of the winds.

“We often only have one observation of a particular object, then several months or even years later we observe it again and see if there’s been a change,” says Dr Michael Parker of the Institute of Astronomy at the University of Cambridge, UK, lead author on a paper published in Nature this week which describes the discovery.

“Thanks to this long observation campaign, we observed changes in the winds on a timescale of less than an hour for the first time.”

The changes were seen in the increasing temperature of the winds, a signature of their response to greater X-ray emission from the disc right next to the black hole.

Furthermore, the observations also revealed changes to the chemical fingerprints of the outflowing gas: as the X-ray emission increased, it stripped electrons in the wind from their atoms, erasing the wind signatures seen in the data.

“The chemical fingerprints of the wind changed with the strength of the X-rays in less than an hour, hundreds of times faster than ever seen before,” says co-author Professor Andrew Fabian, also from the Institute of Astronomy, and principal investigator on the project.

“It allows us to link the X-ray emission arising from the material falling into the black hole, to the variability of the outflowing wind farther away.”

Dr Parker adds: “Black hole winds are one of the mechanisms for feedback, where the energy coming out from the black hole regulates the growth of the host galaxy. Understanding these winds is crucial to understanding how galaxies, including our own, grow.”

Michael Parker et al: "The response of relativistic outflowing gas to the inner accretion disk of a black hole" Nature 2 March 2017

Adapted from a press release by the European Space Agency

Astronomers have made the most detailed observation yet of an ultra-fast wind emanating from a Black Hole at a quarter of the speed of light. Using the European Space Agency (ESA)’s XMM-Newton and NASA’s NuSTAR telescopes, the scientists observed the phenomenon in an active galaxy known as IRAS 13224-3809.

Understanding these winds is crucial to understanding how galaxies, including our own, growDr Michael ParkerEuropean Space Agency (ESA)Artist's impression of the winds emanating from the supermassive black hole


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