Astronomy Picture of the Day · January 13, 2001

A Sky Full Of Hydrogen

The Astronomy Picture of the Day for January 13, 2001 is “A Sky Full Of Hydrogen,” an image. It is credited to Credits: J. Dickey ( UMn ), F. Lockman ( NRAO ), SkyView. The original explanation runs about 175 words.

From the 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, January 13, 2001

Read the full explanation on science.nasa.gov

At a glance

Date: January 13, 2001
Type: Image
Credit: Credits: 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 175 words

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On this day: January 13 in other years

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Source

Astronomy Picture of the Day, January 13, 2001 — science.nasa.gov/image-article/apod-2001-january-13-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.