Science Daily - August 20, 2007
Using NASA's Swift satellite, McGill University and Penn State University astronomers have identified an object that is likely one of the closest neutron stars to Earth -- and possibly the closest.
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The team next targeted Calvera with the 8.1-meter Gemini North Telescope in Hawaii. These observations, along with a short observation by NASA's Chandra X-ray Observatory, showed that the object is not associated with any optical counterpart down to a very faint magnitude. Chandra's sharper X-ray vision sees the object as point-like, consistent with the neutron-star interpretation.
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