Astronomy Picture of the Day · July 25, 1999

The Cygnus Loop

The Astronomy Picture of the Day for July 25, 1999 is “The Cygnus Loop,” an image. It is credited to Credit: J. Hester (ASU), NASA. The original explanation runs about 105 words.

From the explanation

“The shockwave from a 20,000 year-old supernova in the constellation of Cygnus supernova explosion is still expanding into interstellar space.”

— APOD editors, July 25, 1999

Read the full explanation on science.nasa.gov

At a glance

Date: July 25, 1999
Type: Image
Credit: Credit: J. Hester (ASU), NASA
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 105 words

All of July 1999 → · 1999 by month → · Full archive since 1995 →

Topics in this entry

Nebulae Supernovae

Topics are matched from words in the title and explanation.

On this day: July 25 in other years

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Source

Astronomy Picture of the Day, July 25, 1999 — science.nasa.gov/image-article/apod-1999-july-25-the-cygnus-loop

Copy taken Oct 28, 2026, 2:39 AM EDT. The image and explanation belong to their creators. OpenOrbit is not affiliated with or endorsed by NASA.