NASA’s Chandra Observatory Detects Milky Way Supernova
By Space Coast Daily // August 7, 2013
26,000 light years away
(VIDEO: Alton Parrish)
BREVARD COUNTY • KENNDY SPACE CENTER, FLORIDA – Remnants from the newest supernova and black hole in the Milky Way Galaxy have been detected by NASA’s Chandra X-ray observatory.
Images NASA’s Chandra X-ray Observatory in blue and green, radio data from the NSF’s Very Large Array in pink, and infrared data from Caltech’s Palomar Observatory in yellow have given astronomers the clearest photo of the supernova remnant called W49B.
It is about a thousand years old, as seen from Earth, and is at a distance about 26,000 light years away.
Supernova explosions that destroy massive stars are generally symmetrical, with the stellar material blasting away more or less evenly in all directions.
However, in the W49B supernova, material near the poles of the doomed rotating star was ejected at a much higher speed than material emanating from its equator. Jets shooting away from the star’s poles mainly shaped the supernova explosion and its aftermath.
By tracing the distribution and amounts of different elements in the stellar debris field, researchers were able to compare the Chandra data to theoretical models of how a star explodes.
For example, they found iron in only half of the remnant while other elements such as sulfur and silicon were spread throughout. This matches predictions for an asymmetric explosion. Also, W49B is much more barrel-shaped than most other remnants in X-rays and several other wavelengths, pointing to an unusual demise for this star.
Most of the time, massive stars that collapse into supernovas leave a dense spinning core called a neutron star.
Astronomers can often detect these neutron stars through their X-ray or radio pulses, although sometimes an X-ray source is seen without pulsations. A careful search of the Chandra data revealed no evidence for a neutron star, implying an even more exotic object might have formed in the explosion, that is, a black hole.
This may be the youngest black hole formed in the Milky Way galaxy, with an age of only about a thousand years, as viewed from Earth.
A well-known example of a supernova remnant in our galaxy that likely contains a black hole is SS433. This remnant is thought to have an age between 17,000 and 21,000 years, as seen from Earth, making it much older than W49B.
The new results on W49B, which were based on about two-and-a-half days of Chandra observing time, were published in a paper in the Feb. 10, 2013 issue of the Astrophysical Journal.
NASA’s Chandra X-ray Observatory is a telescope specially designed to detect X-ray emission from very hot regions of the Universe such as exploded stars, clusters of galaxies, and matter around black holes. Because X-rays are absorbed by Earth’s atmosphere, Chandra must orbit above it, up to an altitude of 86,500 miles in space.
The Chandra X-ray Observatory was launched and deployed by Space Shuttle Columbia on July 23, 1999.