#MessierMonday No. 103

This week’s #MessierMonday is M103, aka NGC 581. It’s an open cluster in the constellation Cassiopeia. See how the stars sparkle like gemstones in the sky.
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Image: Donald Pelletier, CC BY-SA 4.0 <https://t.co/0JfKJAy4iE>, via Wikimedia Commons pic.twitter.com/8cUZDirAJs

— Dr Clare Turner (@DrMathsPhysics) December 13, 2021