M7: Ptolemy’s Drop of Scorpion Venom

The star cluster Messier 7.jpgLet’s continue our survey of Messier objects. Check some basic info if you’re joining late here.

Above is another open cluster, like the previous number of this series. Not a pretty name like “Butterfly,” but that of a figure of science from the ancient world. Ptolemy described it as a nebula (Latin for cloud). At a distance of almost a thousand light years, it does take a telescope to discern any of its eighty or so stars.

Does M7 have any scientific significance? Not really. The Hubble Space Telescope hasn’t been aimed there. It is a family of stars all birthed from the same interstellar cloud about two-hundred million years ago. An observer on a planet inside the cluster would have swaths of bright stars spotting the night skies. Some might even be visible in daylight.

As seen from Earth, it appears near the end of Scorpio’s tail, maybe a drop of invertebrate venom. To see it well from the Northern Hemisphere, look well to the south, and only in summer can one see it in dark skies.

Image credit: By Credit: ESO – http://www.eso.org/public/images/eso1406a/ http://www.eso.org/public/archives/images/large/eso1406a.jpg, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=31346316

About catholicsensibility

Todd lives in Minnesota, serving a Catholic parish as a lay minister.
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