From within the city, by the rising moon, I acquired 30×30 seconds, ISO 3200 of the M67. The gear was the usual, N 150/750, Baader MPCC Mark III, Canon 1100D mod, HEQ5, with the IDAS LPS D2 filter. There was light, lamps and a glowing sky (the Pleiades, high up, barely visible to the naked eye) from all over the place, so this is the best I could squeeze out of the conditions.
It is not a remarkable photo target, but the cluster is well studied. It is about the age of the Sun, one of the oldest open clusters known, and scientists think it has lost ninety percent of its mass, and currently has „only” 1400 solar masses. In comparison, the Rosette Nebula is estimated to have 10 thousand solar masses. M67 is at around 2600-2900 light years away.
M 67, NGC 2682, Mel 94, Col 204 [open cluster in Cnc] M. 67. Fine open cluster, typical of Class II. 6.9m ø29′ [wiki] [simbad] 750mm (tovább…)