NGC 129 (also C 0027 +599, OCl 294) is a magnitude +6.5 loose open star cluster located 5,450 light-years away in the constellation Cassiopeia. NGC 129 contains approximately 35 members stars; several of magnitude 8 and 9 with the remaining being magnitude 10 and 11. The Cepheid variable DL Cassiopeiae (HD 236429, 8.7 - 9.3 mag) is a member of the cluster. The cluster lies at the midpoint between beta Cassiopeiae (Caph, mag 2.26) and gamma Cassiopeiae (mag 2.17). The age of the cluster is estimated at around 76 million years.
The cluster was discovered by German-British astronomer William Herschel using a 47.5 cm (18.7 inch) reflecting telescope at Windsor Road, Slough, on the 16th December 1788.
Right Ascension 00h 29m 58s, Declination +60° 12' 40"