July 31, 2012
Chandra Discovers X-Rays Coming From A Young Supernova Remnant
April Flowers for redOrbit.com - Your Universe Online
In a galaxy not that far away, astronomically speaking at least, researchers using NASA's Chandra X-ray Observatory have detected the first x-rays emitted by the debris of a young supernova, SN 1957D.
15 million light years from Earth, in the M83 spiral galaxy, SN 1957D is one of only a few supernova located outside the Milky Way galaxy that is detectable in both radio and optical wavelengths, decades after the explosion itself was observed.
The Chandra X-ray Observatory is a telescope specially designed to detect x-ray emissions from hot regions of the Universe. These hot zones include exploded stars, clusters of galaxies, and black holes. To catch these rays, Chandra orbits Earth at an altitude of 86,500 miles in space. The Smithsonian's Astrophysical Observatory at Harvard University in Cambridge, MA, collects the data and disseminates it to scientists around the world.
This is not the first time the Chandra Observatory has tried to capture x-rays from SN 1957D. In 2000 and 2001, researchers made a relatively short observation of about 14 hours total, but did not detect any x-ray emissions. In 2011 and 2012, they tried again, with much greater success. This time the observation totaled nearly 8 and 1/2 days of Chandra time and it revealed the presences of x-ray emissions.
This latest image from the Chandra telescope shows a full field view of M83 with the low, medium and high-energy X-rays shown in red, green and blue respectively.
The new data suggests that SN 1957D contains a neutron star. A neutron star, also known as a pulsar, is a rapidly spinning dense star formed when the core of pre-supernova collapsed. Neutron stars no longer produce nuclear fusion, which allows gravity to force the star's core to condense inward upon itself. This creates a small star with an extremely high mass, about 1.5 times higher than that of our sun. The neutron star inside of SN 1957D could be producing a cocoon of charged particles moving at close to the speed of light known as a pulsar wind nebula. Pulsar wind nebula are nebula powered by pulsar winds, one of the most famous examples is the Crab Nebula.
If correct, this would date the pulsar in SN 1957D at only 55 years, one of the youngest ever seen. SN 1979C, in the M100 galaxy, might also be in the running for the youngest pulsar but astronomers can't confirm if there is a pulsar or a black hole at the center.
Optical images from the Hubble Telescope shows SN 1957D's debris is located at the edge of a relatively young star cluster less than 10 million years old with stars that have masses about 17 times higher than that of the Sun.
The results of this study will be published in an upcoming issue of The Astrophysical Journal.