The first CCD UBV ( RI ) _ { C } photometric study in the area of the doubtful open cluster NGCÂ 2129 is presented .
Photometry of a field offset 15 arcmin northward is also provided , to probe the Galactic disk population toward the cluster .
Using star counts , proper motions from the UCACÂ 2 catalog , colour-magnitude and colour-colour diagrams we demonstrate that NGCÂ 2129 is a young open cluster .
The cluster radius is 2.5 arcmin , and across this region we find evidence of significant differential reddening , although the reddening law seems to be normal toward its direction .
Updated estimates of the cluster fundamental parameters are provided .
The mean reddening is found to be E ( B - V ) =0.80 \pm 0.08 and the distance modulus is ( m - M ) _ { o } = 11.70 \pm 0.30 .
Hence , NGCÂ 2129 is located at 2.2 \pm 0.2 kpc from the Sun inside the Local spiral arm .
The age derived from 37 photometrically selected members is estimated to be approximately 10 million years .
These stars are used to provide new estimates of the cluster absolute proper motion components .