# Supernova remnant

Also called: SNR.

The expanding debris of a star that exploded as a supernova.

A massive star ends its life in a supernova, an explosion briefly brighter than a whole galaxy. The blast wave sweeps up and heats the surrounding gas, which glows for tens of thousands of years.

The Crab Nebula (M 1) is the remnant of a supernova seen in 1054; the Veil Nebula in Cygnus is the delicate, lacy edge of one that exploded some 10,000–20,000 years ago.

**At the eyepiece:** The Veil is transformed by an OIII [nebula filter](https://astropilot.space/glossary/nebula-filter): without it you may see nothing, with it the filaments look like twisted smoke.

**Examples:** [M1](https://astropilot.space/object/M1.md), [NGC6960](https://astropilot.space/object/NGC6960.md), [NGC6992](https://astropilot.space/object/NGC6992.md), [IC443](https://astropilot.space/object/IC443.md)

**Related:** [Nebula](https://astropilot.space/glossary/nebula.md), [Nebula filter](https://astropilot.space/glossary/nebula-filter.md), [Planetary nebula](https://astropilot.space/glossary/planetary-nebula.md)

From the AstroPilot astronomy glossary: https://astropilot.space/glossary/supernova-remnant