Cygnus Loop

A small part of the Cygnus Loop supernova remnant, which marks the edge of an expanding blast wave from an enormous stellar explosion that occurred about 10,000 years ago. The remnant is located in the constellation Cygnus, the Swan.

Cygnus Loop, group of bright nebulae (Lacework Nebula, Veil Nebula, and the nebulae NGC 6960, 6979, 6992, and 6995) in the constellation Cygnus, thought to be remnants of a supernova—i.e., of the explosion of a star probably 10,000 years ago. The Loop, a strong source of radio waves and X-rays, is still expanding at about 100 km (60 miles) per second. It lies about 1,800 light-years from Earth.

This article was most recently revised and updated by Erik Gregersen.
Citation Information
Article Title: Cygnus Loop
Website Name: Encyclopaedia Britannica
Publisher: Encyclopaedia Britannica, Inc.
Date Published: 05 August 2019
Access Date: March 14, 2025