Astronomy Picture of the Day · December 17, 1999

Hot Gas In Hydra A

The Astronomy Picture of the Day for December 17, 1999 is “Hot Gas In Hydra A,” an image. It is credited to Credit: NASA/ CXC/ SAO. The original explanation runs about 136 words.

From the explanation

“The Hydra A galaxy cluster is really big. In fact, such clusters of galaxies are the largest gravitationally bound objects in the Universe.”

— APOD editors, December 17, 1999

Read the full explanation on science.nasa.gov

At a glance

Date: December 17, 1999
Type: Image
Credit: Credit: NASA/ CXC/ SAO
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 136 words

All of December 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: December 17 in other years

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Source

Astronomy Picture of the Day, December 17, 1999 — science.nasa.gov/image-article/apod-1999-december-17-hot-gas-in-hydra-a

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.