Credit: NASA, ESA, CSA, D. Milisavljevic(Purdue), A. Pagan (STScI)

This image highlights several interesting features of supernova remnant Cassiopeia A as seen with Webb’s NIRCam (Near-Infrared Camera):

NIRCam’s exquisite resolution is able to detect tiny knots of gas, comprised of sulfur, oxygen, argon, and neon from the star itself. Some filaments of debris are too tiny to be resolved even by Webb, meaning they are comparable to or less than 10 billion miles across (around 100 astronomical units). Researchers say this represents how the star shattered like glass when it exploded.

Circular holes visible in the MIRI image within the Green Monster, a loop of green light in Cas A’s inner cavity, are faintly outlined in white and purple emission in the NIRCam image—this represents ionized gas. Researchers believe this is due to the supernova debris pushing through and sculpting gas left behind by the star before it exploded.

This is one of a few light echoes visible in NIRCam’s image of Cas A. A light echo occurs when light from the star’s long-ago explosion has reached, and is warming, distant dust, which is glowing as it cools down.

NIRCam captured a particularly intricate and large light echo, nicknamed Baby Cas A by researchers. It is actually located about 170 light-years behind the supernova remnant.

Provider: Space Telescope Science Institute

Image Source: https://webbtelescope.org/contents/news-releases/2023/news-2023-149

Curator: STScI, Baltimore, MD, USA

Image Use Policy: https://www.stsci.edu/copyright