The star cluster Messier 7

Image Credit & Copyright: European Southern Observatory (ESO) La Silla.

At a distance of 800 light years, were fairly safe from the venomous sting of Scorpius.  That being said, this predatory arthropod that nests near the core of the galaxy has some stunning features that we can review in detail.

This object, Messier 7 is located in the stinger of the scorpion and at an apparent magnitude of 3.3 is easily visible with the naked eye in dark locations.  It’s an open star cluster of about 100 stars that spans roughly 25 light years in diameter.  Many of the stars that make this cluster are a young 200 million years old and they carry a punch that would suit the scorpions sting just fine.  The brightest stars in this cluster, around 10 or so will rapidly burn through their fuel and explode as supernovae.  The rest will begin to drift apart, over time, ending the cluster all together.

So in a few tens of millions of years if you’re still around, look to the tail of the scorpion for some massive fireworks on a cosmic scale.

NAME: M7, Messier 7, NGC 6475.

WHAT IS IT?: Open star cluster.

HOW FAR AWAY IS IT?: 800 light years.

HOW BIG IS IT?: Roughly 100 stars spanning 25 light years.

HOW OLD IS IT?: About 200 million years.

WHO DISCOVERED IT?: 1st to mention it was Cladius Ptolemy around 130 AD.

APPARENT MAGNITUDE?: Easily visible with the naked eye at 3.3 or +3.3.

WHERE IS IT? (General): Constellation Scorpius.

WHERE IS IT? (Exact RA/DEC J2000): RA 17h 53m 51s / DEC -34° 47′ 34.34″.


ESO release of this image:

ESO image page for this image:

Image | This entry was posted in Astronomy (Learning), Astrophotography (DSOs), Images, Star Clusters (Globular-Open), Stars (Non-Sun Related) and tagged , , , , , , , , , . Bookmark the permalink.


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