Atmospheric seeing at Indian Astronomical Observatory

After the availability of a clear sky, seeing is the most important parameter to characterize any new astronomical sites. Considering the need to identify a few good candidate sites for India’s large optical telescope project, we have developed a fully robotic DIMM seeing monitor. Our DIMM system uses a 12-inch Meade telescope, a Lucid Vision CMOS camera, and a varieties of sensors to support fully unmanned operation. One of the DIMM system has been permanently installed at IAO observatory, which is 4500m above sea level whereas, other mobile DIMM systems have been used in campaign mode in the near by mountain peaks as tall as 5300m. Simultaneous measurements of the seeing have been carried at different heights. We present the details of our DIMM systems as well as seeing measurements carried out at IAO Hanle and a few other places. We have also attempted to explore any correlation exist between DIMM seeing with other ground and space based meteorological parameters.