At first glance this week's Palomar Observatory History Photo of the Week might seem like an ordinary vintage shot of the 200-inch telescope and dome. What makes this photo really stand out for me is the person standing in the opening of the dome. Click on the image to embiggen and you'll be able to see him better.
I am not sure who the person is, but this fine photo was taken by O.K. Harter in August of 1941. At the time of this picture the dome was completed and just about all of the work on the telescope was as well. The 200-inch mirror was in the optical shop at Caltech and the concrete dummy mirror was installed on the telescope where the mirror would eventually be.