Anyone who is not shocked by quantum theory has not understood it.
Niels Bohr
- Messier 103 (Wikipedia)
Messier 103 (also known as M103, or NGC 581) is a small open cluster of many faint stars in Cassiopeia. It was discovered on 27 March 1781 by Pierre Méchain, but later added as Charles Messier’s last deep-sky object in his catalogue.