Webb reveals the youngest known supernova remnant in new light

NASA's James Webb Space Telescope has captured incredible details in Cassiopeia A (Cas A), a supernova remnant located about 11,000 light-years from Earth in the constellation Cassiopeia.

Cas A spans approximately 10 light-years and is the youngest known remnant of an exploding, massive star in our Milky Way galaxy. The new mid-infrared image from Webb's Mid-InfraRed Instrument (MIRI) shows the supernova remnant in a new light.

The outer part of the remnant, especially on the top and left, displays curtains of material in shades of red and orange. These hues result from the emission of warm dust and indicate the location where material ejected from the supernova is colliding with the surrounding circumstellar material.

The mottled filaments of bright pink represent material originating from the star itself and are possibly illuminated by a combination of heavy elements and dust emission.

At the centre right, a greenish loop extends from the right side of the ring into the central cavity. The shape and complexity of this loop are unexpected and challenging for scientists to understand.

Stars: always making a dramatic exit! 🌟 Webb’s powerful infrared eye has captured never-before-seen detail of Cassiopeia A (Cas A). 11,000 light-years away, it is the remnant of a massive star that exploded about 340 years ago: https://t.co/LLQsFQJwVQ pic.twitter.com/xqlGFzhYoy

— NASA Webb Telescope (@NASAWebb) April 7, 2023

Supernovae like the one that formed Cassiopeia A (Cas A) are crucial for life because they are responsible for creating many of the elements that make up the universe, including the building blocks of life.

Cas A has been widely studied by a number of ground-based and space-based observatories. By studying Cas A with Webb, astronomers hope to gain a better understanding of its dust content.

"By understanding the process of exploding stars, we’re reading our own origin story. I’m going to spend the rest of my career trying to understand what’s in this data set," said Danny Milisavljevic of Purdue University in West Lafayette, Indiana, principal investigator of the Webb program that captured these observations.