Unusual Shape of Exploded Star Puzzles Scientists

Penn State astronomers have used NASA's Chandra X-ray Observatory to produce a new image of a ghostly exploded star with an unusual shape in a galaxy near the Milky Way. Astronomers think the object may be the remains of a white-dwarf star that disintegrated in a thermonuclear explosion, known as a Type Ia supernova, but it does not look like other likely Type Ia remnants found in our own Milky Way galaxy.

The research that led to the new image of this object was led by Penn State University astronomers Sangwook Park and Jae-Joon Lee, and was presented at the 214th meeting of the American Astronomical Society in Pasadena, California, on 9 June 2009. The strange object, known as SNR 0104-72.3 (SNR 0104 for short), is in the Small Magellanic Cloud galaxy, which is a neighbor of our Milky Way galaxy.

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Geriatric Pulsar Discovered and Found Still Kicking

The oldest isolated pulsar ever detected in X-rays has been found with NASA's Chandra X-ray Observatory by a team of Penn State astronomers led by George Pavlov, professor of astronomy and astrophysics. This very old and exotic object turns out to be surprisingly active. The pulsar, PSR J0108-1431 (J0108) is about 200 million years old. Among isolated pulsars -- those whose spin has not been accelerated within a binary system -- and among pulsars detected with X-rays, it is over 10 times older than the previous record holder. At a distance of 770 light years, it is one of the nearest pulsars known. The surprise came when a team of astronomers led by Pavlov observed J0108 in X-rays with the orbiting Chandra X-ray observatory. They found that this pulsar glows much brighter in X-rays than was expected for a pulsar of such advanced years. "This pulsar is pumping out high-energy radiation much more efficiently than its younger cousins," said Pavlov.
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