The week in pictures: July 14–20, 2012
In the past seven days, scientists discovered a grand design spiral galaxy in the early universe, the Spitzer Space Telescope nabbed its first exoplanet candidate, Cassini witnessed daytime lightning on Saturn, and more.
NASA/JPL-Caltech/Space Science Institute
Cassini spots daytime lightning on Saturn
Scientists have deduced that the lightning bolts originate in the clouds
deep down in Saturn's atmosphere where water droplets freeze. Learn more »