Abstract:
CCD observations of the open cluster NGC 2453 have been carried out in B, V and I passbands. A total of 356 stars have been observed in a field of about 4'x6' of the sky centred on the cluster. Colour-magnitude diagrams in V, B-V and V, V-I have been generated down to V=20 and for the first time, the unevolved part of the cluster main sequence has been observed. The mean true distance modulus derived from these diagrams is 13.mag 85+/-0.2 yielding a distance of 5.9+/-0.2kpc. A mean age of 25Myr has been derived for the cluster by fitting isochrones. The distance of approximately 6kpc puts the cluster much beyond the planetary nebula NGC 2452 whose largest estimated distance to date is about 3.5kpc. The two are not physically associated.
