Astronomy Picture of the Day ·

M13: The Great Globular Cluster in Hercules

The Astronomy Picture of the Day for May 20, 2021 is “M13: The Great Globular Cluster in Hercules,” an image. The picture is copyrighted by its creator (Image Credit & Copyright: Martin Dufour). The original explanation runs about 154 words.

M13: The Great Globular Cluster in Hercules
Credit: Image Credit & Copyright: Martin Dufour Copyrighted Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“In 1716 , English astronomer Edmond Halley noted, “This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent.” Of course, M13 is now less modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the northern sky.”

— APOD editors, May 20, 2021

Read the full explanation on science.nasa.gov

At a glance

Date
May 20, 2021
Type
Image
Credit
Credit: Image Credit & Copyright: Martin Dufour
Copyright
Copyrighted by the credited creator. Ask the copyright holder before reusing it.
Explanation length
About 154 words

All of May 2021 → · 2021 by month → · Full archive since 1995 →

Topics in this entry

The MoonStar clusters

Topics are matched from words in the title and explanation.

On this day: May 20 in other years

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Source

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.