Webb’s powerful infrared eye has captured never-before-seen detail of Cassiopeia A (Cas A), the remnant of a massive star that exploded about 340 years ago — from our perspective here on Earth. (Despite being 11,000 light-years away, this supernova may have been visible to the naked eye, something that has not been seen in our galaxy since.)

Let’s dissect the image: The exterior, left side of the image (shown in orange) marks where ejected material from the exploded star is ramming into surrounding gas and dust. Within that outer shell is material from the star itself, including elements like oxygen, argon and neon. What’s that green loop on the right? Scientists are still puzzling out its unexpected shape and complexity.

As the youngest known remnant from an exploded, massive star in our galaxy, Cas A offers unique clues into a star’s death. By studying Cas A, Webb astronomers may also learn more about the origins and production of cosmic dust — which forms the elements we’re made of.

Credit: NASA, ESA, CSA, D. Milisavljevic (Purdue), T. Temim (Princeton), I. De Looze (Ghent University), with image processing by J. DePasquale (STScI)

Remnant Star SNR 0509-68.7

Can you spot the supernova remnant? SNR 0509-68.7 is the bright, irregular region of reddish dust near the upper center. After a star’s explosive death in a supernova, the left-behind gas and dust are known as a supernova remnant.
The one seen in this HubbleClassic image resides about 160,000 light-years away in the Large Magellanic Cloud, which is a neighboring galaxy to our own Milky Way.

Remnant Star Puppis A

Supernova explosions forge heavy elements, providing raw material from which future generations of stars & planets can form! Puppis A, the remains of a supernova explosion, is about 7,000 light years from Earth and roughly 100 light years wide!

Remnant Star DEM L 190

Beauty in the chaos! These colorful shreds of cosmic material are the “leftovers” of a massive star’s supernova explosion! Known as DEM L 190, this bright supernova remnant resides about 160,000 light-years from Earth in the constellation Dorado.

Image credit: ESA/Hubble & NASA, S. Kulkarni, Y. Chu