Astronomy Picture of the Day · April 4, 1999

Hot Gas and Dark Matter

The Astronomy Picture of the Day for April 4, 1999 is “Hot Gas and Dark Matter,” an image. It is credited to Credit: Richard Mushotzky (GSFC/NASA), ROSAT, ESA, NASA. The original explanation runs about 96 words.

From the explanation

“Is the gravity of the galaxies seen in this image high enough to contain the glowing hot gas? Superposed on an optical picture of a group of galaxies is an image taken in X-ray light.”

— APOD editors, April 4, 1999

Read the full explanation on science.nasa.gov

At a glance

Date: April 4, 1999
Type: Image
Credit: Credit: Richard Mushotzky (GSFC/NASA), ROSAT, ESA, NASA
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 96 words

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

Topics in this entry

Galaxies

Topics are matched from words in the title and explanation.

On this day: April 4 in other years

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Source

Astronomy Picture of the Day, April 4, 1999 — science.nasa.gov/image-article/apod-1999-april-04-hot-gas-and-dark-matter

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.