M11: open cluster distance measurement [Observed: 23 June 2006]
The M11 open cluster (Wild Duck cluster, NGC6705) is observed through B and V filters. An HR diagram is constructed. It is compared with an absolute HR diagram made from Hipparcos data which measured the parallaxes of nearby stars. The distance to M11 is then derived. The interstellar extinction is taken into account using the Henden's sequence for M11 (U data).