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Super-Earth Detected in Cool Star’s Habitable Zone

February 2, 2012 Leave a comment

Image: Guillem Anglada-Escudé.

Image: Guillem Anglada-Escudé.

An international team of scientists led by Carnegie’s Guillem Anglada-Escudé and Paul Butler has discovered a potentially habitable super-Earth orbiting a nearby star. The star is a member of a triple star system and has a different makeup than our Sun, being relatively lacking in metallic elements. This discovery demonstrates that habitable planets could form in a greater variety of environments than previously believed. Their work will be published by The Astrophysical Journal Letters and the current version of the manuscript will be posted athttp://arxiv.org/archive/astro-ph

The team used public data from the European Southern Observatory and analyzed it with a novel data analysis method. They also incorporated new measurements from the Keck Observatory’s High Resolution Echelle Spectrograph and the new Carnegie Planet Finder Spectrograph at the Magellan II Telescope.

Their planet-finding technique involved measuring the small wobbles in a star’s orbit in response to a planet’s gravity. Anglada-Escudé and his team focused on an M-class dwarf star called GJ 667C, which is 22 light years away. It is a member of a triple-star system. The other two stars (GJ 667AB) are a pair of orange K dwarfs, with a concentration of heavy elements only 25% that of our Sun’s. Such elements are the building blocks of terrestrial planets so it was thought to be unusual for metal-depleted star systems to have an abundance of low mass planets.

Full Story: http://carnegiescience.edu/news/new_superearth_detected_within_habitable_zone_nearby_cool_star

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Do Black Holes Help Stars Form?

February 2, 2012 1 comment

The centre of just about every galaxy is thought to host a black hole, some with masses of thousands of millions of Suns and consequently strong gravitational pulls that disrupt material around them. They had been thought to hinder the birth of stars, but now an international team of astronomers studying the nearby galaxy Centaurus A has found quite the opposite: a black hole that seems to be helping stars to form. The team, led by Dr Stanislav Shabala of the University of Tasmania, Dr Mark Crockett of the University of Oxford, and Dr Sugata Kaviraj of Imperial College, London, publish their results in the journal Monthly Notices of the Royal Astronomical Society.

Black holes at the centre of galaxies ‘switch on’ from time to time, driving material around them into outflows that can stretch for millions of light years. The flows plough through galactic gas, compressing, heating and pushing it out of the way. Much of this gas is the raw material from which stars are made, so the outflows significantly affect star formation in the galaxies that host them.

Full Story: http://www.ras.org.uk/news-and-press/219-news-2012/2070-do-black-holes-help-stars-form

GRAIL Returns Its 1st Video from Lunar Far Side

February 2, 2012 Leave a comment

Image credit: NASA/Caltech-JPL

Image credit: NASA/Caltech-JPL

A camera aboard one of NASA’s twin Gravity Recovery And Interior Laboratory (GRAIL) lunar spacecraft has returned its first unique view of the far side of the moon. MoonKAM, or Moon Knowledge Acquired by Middle school students, will be used by students nationwide to select lunar images for study.

GRAIL consists of two identical spacecraft, recently named Ebb and Flow, each of which is equipped with a MoonKAM. The images were taken as part of a test of Ebb’s MoonKAM on Jan. 19. The GRAIL project plans to test the MoonKAM aboard Flow at a later date.

To view the 30-second video clip, visit: http://go.nasa.gov/zZXAPs .

Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2012-031

Remnant of an Explosion with a Powerful Kick?

February 2, 2012 Leave a comment

Image Credit: X-ray: NASA/CXC/SAO/I.Lovchinsky et al, IR: NASA/JPL-Caltech

Image Credit: X-ray: NASA/CXC/SAO/I.Lovchinsky et al, IR: NASA/JPL-Caltech

Vital clues about the devastating ends to the lives of massive stars can be found by studying the aftermath of their explosions. In its more than twelve years of science operations, NASA’s Chandra X-ray Observatory has studied many of these supernova remnants sprinkled across the Galaxy.

The latest example of this important investigation is Chandra’s new image of the supernova remnant known as G350.1+0.3. This stellar debris field is located some 14,700 light years from the Earth toward the center of the Milky Way.

Evidence from Chandra and from ESA’s XMM-Newton telescope suggest that a compact object within G350.1+0.3 may be the dense core of the star that exploded. The position of this likely neutron star, seen by the arrow pointing to “neutron star” in the inset image, is well away from the center of the X-ray emission. If the supernova explosion occurred near the center of the X-ray emission then the neutron star must have received a powerful kick in the supernova explosion.

Full Story: http://www.nasa.gov/mission_pages/chandra/multimedia/g350.html