NASA's Cassini Spacecraft Captures an Image of Uranus
Posted on May 4, 2014
NASA's Cassini spacecraft has captured an image of Uranus. Uranus was 93,000,000 miles from Cassini and Saturn when the photo was taken. The planet appears as a blue dot in the distance. Carl Sagan refers to Earth as a pale blue dot in the Cosmos series. In this case the blue dot is Uranus. You can view a larger version of the above image here.
NASA says Uranus appears blue in the natural color image because its visible atmosphere "contains methane gas and few aerosols or clouds." Methane on Uranus absorbs red wavelengths of incoming sunlight, but allows blue wavelengths to escape back into space.