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Archive for March 8, 2013

Southampton Scientist Investigates Russian Meteor


Dr Hugh Lewis, Lecturer in Aerospace Engineering, has analysed the recent extraordinary Russian meteor event using the “NEOImpactor” tool, which was developed by researchers from the University and designed to investigate the risks faced by the Earth from asteroid impacts.

On the morning of Friday 15 February, an asteroid estimated to be the size of a five-storey building entered the atmosphere over the Urals region of Russia and disintegrated. It generated a blastwave that blew out windows and damaged buildings in the city of Chelyabinsk, injuring more than 1000 people. Just a few hours later, the world witnessed the 40 metre asteroid 2012 DA14 pass between the Earth and the ring of geostationary satellites; the closest approach of an object this size for a century.

Dr Lewis explained the significance of the event: “This is the first time that we’ve seen injuries resulting from a collision between the Earth and an asteroid. I think that what surprised most people was the scale of the damage from a relatively small object and the fact that we didn’t have any warning.”

Full Story: http://www.southampton.ac.uk/mediacentre/features/hugh_lewis_russian_meteor.shtml

Iowa State Engineers Developing Ideas, Technologies To Save The Earth From Asteroids


You want to protect the Earth from asteroids? Where were you when the dinosaurs needed you? You want to be like Bruce Willis in that asteroid movie?

Wie has a serious reply: After five years of science and engineering work, Wie and his small team have a publication list of 40-plus technical papers, $600,000 of NASA research support and a proposal for a $500 million test launch of an asteroid intercept system. Plus, Wie has just been invited to show off his research as part of NASA’s Technology Day on the Hill in Washington, D.C., on April 17.

“It’s not a laughing matter,” said Wie, the director of the Asteroid Deflection Research Center at Iowa State University and the Vance D. Coffman Faculty Chair and professor of aerospace engineering.

Recent events have certainly highlighted the threat of asteroid strikes. There was the 15-meter (49-foot) meteor that exploded an estimated 12 miles over Chelyabinsk, Russia, on Feb. 15, damaging buildings and injuring more than 1,000 people. That same day, the 45-meter (148-foot) asteroid 2012 DA14 passed within 17,200 miles of Earth.

Full Story: http://www.news.iastate.edu/news/2013/03/06/asteroiddeflection

Probing Extreme Matter Through Observations Of Neutron Stars


Credits: NASA/CXC/Michigan State/A.Steiner et al

Credits: NASA/CXC/Michigan State/A.Steiner et al

Neutron stars, the ultra-dense cores left behind after massive stars collapse, contain the densest matter known in the Universe outside of a black hole. New results from Chandra and other X-ray telescopes have provided one of the most reliable determinations yet of the relation between the radius of a neutron star and its mass. These results constrain how nuclear matter – protons and neutrons, and their constituent quarks – interact under the extreme conditions found in neutron stars.

Because the mass and radius of a neutron star is directly related to interactions between the particles in the interior of the star, the latest results give scientists new information about the inner workings of neutron stars.

The new values for the neutron star’s structure should hold true even if matter composed of free quarks exists in the core of the star. Quarks are fundamental particles that combine to form protons and neutrons and are not usually found in isolation. It has been postulated that free quarks may exist inside the centers of neutron stars, but no firm evidence for this has ever been found.

Full Story & Image: http://www.chandra.si.edu/photo/2013/47tuc/
Also: http://www.nasa.gov/mission_pages/chandra/multimedia/x7.html

Modeling Jupiter And Saturn’s Possible Origins


New theoretical modeling by Carnegie’s Alan Boss provides clues to how the gas giant planets in our solar system—Jupiter and Saturn—might have formed and evolved. His work was published recently by The Astrophysical Journal.

Boss developed highly detailed, three dimensional models demonstrating that regardless of how gas giant planets form, they should have been able to survive periodic outbursts of mass transfer from the gas disk onto the young star. One model similar to our own Solar System was stable for more than 1,000 years, while another model containing planets similar to our Jupiter and Saturn was stable for more than 3,800 years. The models showed that these planets were able to avoid being forced to migrate inward to be swallowed by the growing proto-sun, or being tossed completely out of the planetary system by close encounters with each other.

“Gas giant planets, once formed, can be hard to destroy,” said Boss, “even during the energetic outbursts that young stars experience.”

Full Story: http://carnegiescience.edu/news/modeling_jupiter_and_saturn’s_possible_origins

Curtains Down For The Black Hole Firewall Paradox: Making Gravity Safe For Einstein Again


Research by scientists at the University of York has revealed new insights into the life and death of black holes.

Their findings dispel the so-called firewall paradox which shocked the physics community when it was announced in 2012 since its predictions about large black holes contradicted Einstein’s crowning achievement – the theory of general relativity. Those results suggested that anyone falling into a black hole would be burned up as they crossed its edge – the so-called event horizon.

Now Professor Sam Braunstein and Dr Stefano Pirandola have extinguished the fire. In a paper published in Physical Review Letters, they invoke quantum information theory, a modern branch of quantum mechanics that treats light and atoms as carriers of information. The key insight from quantum mechanics is the existence of `spooky’ quantum entanglement across a black hole’s event horizon.

Professor Braunstein says: “Quantum mechanics shows that entanglement can exist across the event horizon, between particles inside and outside the black hole. But should this entanglement ever vanish, a barrier of energetic particles would be created: an energetic curtain (or firewall) would descend around the horizon of the black hole. … Our results not only back up Einstein’s theory of gravity, but also point to quantum information theory as a powerful tool for disentangling the deep mysteries of the Universe.”

Full Story: http://www.york.ac.uk/news-and-events/news/2013/research/black-hole-firewall/

Slooh Space Camera To Track Newly Discovered Near-Earth Object 2013 ET Zooming By Earth At Only 2.5 Lunar Distances Away


Discovered on March 3, 2013, by the Catalina Sky Survey, NEO (near-Earth object) 2013 ET, an asteroid the size of a city block, will make its closest approach to Earth on Saturday, March 9th, less than 7 days after it was discovered. Slooh Space Camera will cover its closest approach on Saturday, live on Slooh.com, free to the public, starting at 12:15 p.m. PST / 3:15 p.m. EST / 20:15 UTC — International times at http://goo.gl/kQJuL — accompanied by real-time discussions with Slooh president Patrick Paolucci, Slooh engineer Paul Cox, and documentary filmmaker Duncan Copp. Viewers can watch live on their PC/MAC or iOS/Android mobile device.

The asteroid is estimated to be approximately 64-140 meters (210-460 feet) wide and will pass 2.5 times the Moon’s distance from our planet. At its maximum brightness on March 9th, NEO 2013 ET will be at a relatively dim magnitude of 17 — not bright enough to view through a backyard telescope, but should be reasonably bright through Slooh telescopes in the Canary Islands, off the coast of west Africa.

Full Story (on downloaded PDF): http://goo.gl/4rwnv
Video Of Asteroid: http://youtu.be/cxUabVxRN-g

CSI: Milky Way


Artist’s illustration. Credit: Julie Turner, Vanderbilt University

Artist’s illustration. Credit: Julie Turner, Vanderbilt University

These days the core of the Milky Way galaxy is a pretty tame place…cosmically speaking. The galactic black hole at the centre is a sleeping giant. Existing stars are peacefully circling. Although conditions are favourable, there doesn’t even seem to be much new star formation going on. But there is growing evidence that several million years ago the galactic centre was the site of all manner of celestial fireworks. A pair of assistant professors – Kelly Holley-Bockelmann at Vanderbilt and Tamara Bogdanović at Georgia Institute of Technology – has come up with an explanation that fits these “forensic” clues.

Writing in the March 6 issue of the Oxford University Press journal Monthly Notices of the Royal Astronomical Society, the astronomers describe how a single event – a violent collision and merger between the galactic black hole and an intermediate-sized black hole in one of the small “satellite galaxies” that circle the Milky Way – could have produced the features that point to a more violent past for the galactic core.

“Tamara and I had just attended an astronomy conference in Aspen, Colorado, where several of these new observations were announced,” said Holley-Bockelmann. “It was January 2010 and a snow storm had closed the airport. We decided to rent a car to drive to Denver. As we drove through the storm, we pieced together the clues from the conference and realized that a single catastrophic event – the collision between two black holes about 10 million years ago – could explain all the new evidence.”

Full Story: http://www.ras.org.uk/news-and-press/224-news-2013/2227-csi-milky-way
Also: http://news.vanderbilt.edu/2013/03/csi-milky-way/