Astronomy Picture of the Day

Explanation: Stars, like people, do not always go gentle into that good night. The above Keyhole Nebula results from dying star Eta Carinae's violently casting off dust and gas during its final centuries. Eta Carinae is many times more massive than our own Sun, and should eventually undergo a tremendous supernova explosion. Eta Carinae emits much light in colours outside the human visible range. This past week, X-ray emission from Eta Carinae was verified by the orbiting Rossi X-Ray Timing Explorer to be periodic, peaking every 85.1 days. This, along with a previously hypothesized 5.52 year period, indicates that the dying star might be part of a multiple star system.