Astronomy Picture of the Day · December 18, 1996

A Sky Full Of Hydrogen

The Astronomy Picture of the Day for December 18, 1996 is “A Sky Full Of Hydrogen,” an image. It is credited to A Sky Full Of Hydrogen Credit: J. Dickey (UMn), F. Lockman (NRAO), SkyView. The original explanation runs about 176 words.

From the explanation

“Explanation : Interstellar space is filled with extremely tenuous clouds of gas which are mostly Hydrogen. The neutral hydrogen atom (HI in astronomer’s shorthand) consists of 1 proton and 1 electron.”

— APOD editors, December 18, 1996

Read the full explanation on science.nasa.gov

At a glance

Date: December 18, 1996
Type: Image
Credit: Credit: A Sky Full Of Hydrogen Credit: J. Dickey (UMn), F. Lockman (NRAO), SkyView
Copyright: No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length: About 176 words

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Source

Astronomy Picture of the Day, December 18, 1996 — science.nasa.gov/image-article/apod-1996-december-18-a-sky-full-of-hydrogen

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.