July 20, 2003
The above photo shows a cumulus congestus cloud positioned in front of the Sun. Since this cloud is back-lit, we can see its "silver lining." This cumulus cloud is thick, and thus its underside appears dark, but since the edges are relatively thin, sunlight is scattered forward. This isn't a rare sight, you just have to be at the right place at the right time -- and be sure to look up.