There’s an odd quirk to a tremendous shock wave going through a gas cloud left behind after a star’s catastrophic death: recent research shows that part of it is flowing in the wrong way.
Authors of this study term this phenomenon a “backward shock,” in which a portion of the shock wave returns to where it began, toward the source of the star explosion or supernova.
Located in the region Cassiopeia, the Cassiopeia A supernova nebula is among the nearest leftovers of a supernova to our planet. Neptune is composed of gas that was released before to and during the outburst that tore apart the parent star. A shock wave is still reverberating through the gas as a result of that explosion, and theoretical models predict that this blast wave should continue growing uniformly, like a flawlessly spherical balloon that is always being filled. Scientists, however, discovered that this was not the situation at all.
Scientists used X-ray photos from NASA’s Chandra X-ray Observatory, an orbiting observatory, to examine the shock wave’s trajectory in the new research. After 19 years of observation, the data showed that the western area of the blast wave was actually receding in the other direction, resulting in a reverse shockwave.
Although scientists predicted that the shock wave’s outer layer would grow at a slower pace, they discovered that it was growing at a quicker rate than projected.
A collision with a shell of gas expelled by the sun before it burst is the most plausible scenario, according to the scientists. The scientists also believe that the asymmetrical blast wave might be explained by the peculiar manner in which the initial star perished.
The findings were published in arXiv.
