NGC 637 (also Collinder 17, OCL 329) is a magnitude +8.2 open star cluster located 7,045 light-years away in the constellation Cassiopeia.
The cluster was discovered by the German-British astronomer William Herschel using a 47.5 cm (18.7 inch) f/13 speculum reflector at Windsor Road, Slough, on the 9th November 1787.
Right ascension 01h 43m 04s, Declination +64° 02' 24"
The estimated age of this cluster is 515 million years. Read more