Stellar Science

What Happens After a Supernova Blows? Watch and Find Out

New time-lapse videos from the Chandra X-ray Observatory show the Crab Nebula and the Cassiopeia A supernova remnant over more than 20 years.

round, expanding shell with intricate, knotty filaments

Stellar Science

Cassiopeia A: A Festive Supernova Remnant

New near-infrared observations from the Webb telescope reveal intricate strands of debris from the exploded star.

A star goes poof!

Deep Sky

Seeking Cas A, the Ghostly Remains of a Mysterious Supernova

We still don't know for sure if anyone saw the supernova explosion in Cassiopeia around 1680, but there's no question we can observe what remains of it today.

Stellar Science

Quark Nova Spotted in Cas A?

Two elements deep within Cassiopeia A, hint the supernova remnant underwent a quark nova — a theoretical second explosion that leaves behind a quark star — just days after the original supernova.

Stellar Science

Cassiopeia A in 3D

Explore a supernova remnant with this fun interactive simulation, created from detailed space- and ground-based observations in multiple wavelengths.