Located 26,000 light-years away in the northern constellation Aquila, W49B is a snapshot of the shock waves from a star that went supernova an estimated 1,000 years ago (not including the time it took for its light to reach us). Several observation methods and instruments were used to create the technicolor image above – X-rays from NASA’s Chandra X-ray Observatory shown in blue and green, radio data from the National Science Foundation’s Very Large Array in pink, and infrared and optical data from the Palomar Observatory in orange and yellow — but put all together, one feature becomes glaringly obvious.
This thing is a mess.
Typically, supernova remnants have a roughly circular or shell-like shape, generally seen as a ring of bright material surrounding the dense burnt-out core of a star. The ring is bright because it’s composed of interstellar gas and dust that’s being violently ionized by the spreading force of the supernova. Ionized material gives off many forms of radiation, detectable in various wavelengths by observatories on the ground, as well as in space.
W49B isn’t a ring, though. It’s a sloppy barrel shape that indicates an uneven, asymmetrical eruption, hinting that the original star didn’t go peacefully into this good night.
And as for the star? It’s nowhere to be found — which is in itself strange. Supernova remnants usually have some form of neutron star at their centers, the wildly-spinning, ultra-dense cores of dead massive stars. But even after searching for one, scientists have found no such object at the center of W49B. This could mean that there’s a very different sort of stellar corpse lurking there — a black hole.
If that is indeed the case, then this would be the galaxy’s newest black hole — at least as far as what’s been discovered so far. A mere thousand years old, an alleged black hole at the heart of W49B would have just been born in the night sky around the same time that Vikings were first setting foot on North American shores.
Read more at Discovery News
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