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We present initial results on some of the properties of open clusters NGC6791 and NGC 6819 derived from asteroseismic data obtained by NASA's Keplermission. In addition to estimating the mass, radius and log g of stars on thered-giant branch of these clusters, we estimate the distance to the clustersand their ages. Our model-independent estimate of the distance modulus of NGC6791 is (m-M)_0= 13.11\pm 0.06. We find (m-M)_0= 11.85\pm 0.05 for NGC 6819.The average mass of stars on the red-giant branch of NGC 6791 is 1.20 \pm 0.01M_sun, while that of NGC 6819 is 1.68\pm 0.03M_sun. It should be noted that wedo not have data that cover the entire red-giant branch and the actual masswill be somewhat lower. We have determined model-dependent estimates of ages ofthese clusters. We find ages between 6.8 and 8.6 Gyr for NGC 6791, however,most sets of models give ages around 7Gyr. We obtain ages between 2 and 2.4 Gyrfor NGC 6819.

Sounding open clusters: asteroseismic constraints from Kepler on the properties of NGC 6791 and NGC 6819