For the first time, astronomers have used data from NASA’s Chandra X-ray Observatory and the James Webb Space Telescope to examine Cassiopeia A, a well-known supernova remnant. The study provides new insights into a feature dubbed the "Green Monster", originally observed by Webb in 2023.
Analysis indicates that the Green Monster is likely caused by a blast wave from the supernova striking material around the star, rather than being composed of inner debris. This conclusion builds on earlier interpretations made from Webb’s infrared data.
A multi-layered image of Cassiopeia A has been released, combining X-rays from Chandra, infrared from Webb and Spitzer, and optical data from Hubble. The image reveals various elements and temperature zones within the remnant.
Chandra data shows regions rich in silicon and iron from the exploded star, with outer arcs representing high-energy electrons moving along magnetic fields. These electrons produce X-rays in both interior and peripheral areas.
Webb’s infrared view reveals cooler, undisturbed supernova material, while Chandra captures hot gas affected by shockwaves. This comparison allows researchers to distinguish between processed and untouched remnants of the explosion.
Researchers used NuSTAR to map radioactive titanium and Chandra to locate iron from decayed nickel. Some central filaments of pristine debris seen by Webb are linked to iron-rich regions further out, suggesting radioactive influence on debris structure.
The study suggests that cavities in the debris may have formed from violent mixing of radioactive material with the star’s inner layers during core collapse. These results were presented at the American Astronomical Society meeting and submitted for peer review.