Astronomy Picture of the Day ·

M55: Globular Star Cluster

The Astronomy Picture of the Day for September 18, 2004 is “M55: Globular Star Cluster,” an image. It is credited to Credit: B.J. Mochejska (CfA), J. Kaluzny ( CAMK ), 1m Swope Telescope. The original explanation runs about 143 words.

M55: Globular Star Cluster
Credit: B.J. Mochejska (CfA), J. Kaluzny ( CAMK ), 1m Swope Telescope Shown from science.nasa.gov. Not hosted by OpenOrbit.

From the explanation

“The fifty-fifth entry in Charles Messier’s catalog, M55 is a large and lovely globular cluster of around 100,000 stars. Only 20,000 light-years away in the constellation Sagittarius , M55 appears to earth-bound observers to be nearly 2/3 the size of the full moon.”

— APOD editors, September 18, 2004

Read the full explanation on science.nasa.gov

At a glance

Date
September 18, 2004
Type
Image
Credit
Credit: B.J. Mochejska (CfA), J. Kaluzny ( CAMK ), 1m Swope Telescope
Copyright
No copyright notice on the entry. Check the credited institution’s own usage rules before reusing it.
Explanation length
About 143 words

All of September 2004 → · 2004 by month → · Full archive since 1995 →

Topics in this entry

Star clusters

Topics are matched from words in the title and explanation.

On this day: September 18 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.