The results appear this month in the planetary-science journal Icarus. At 3,200 miles in diameter, Titan is larger than the planet Mercury and is the only body in the solar system with a nitrogen-rich atmosphere like the Earth's. Observing Titan is extremely difficult. High in Titan's atmosphere, ultraviolet light changes methane gases into a thick smog-like organic haze that hides Titan's surface. When the Voyager spacecraft passed by in 1980, it saw only the orange-brown top of Titan's smoggy skies.
Infrared light can penetrate the smog to see Titan's surface.
Unfortunately, Titan is so far away that conventional telescopes see only a fuzzy blob because the image is blurred by Earth's atmosphere. With the tremendous power of the Keck Telescope we are able to map surface features 150 miles in size on a moon that is more than 800 million miles from Earth. I telescope, the world's largest, on Mauna Kea, Hawaii. UCLA Professor Andrea Ghez was a pioneer in applying this technique to infra-red astronomy. Livermore's Gibbard worked with Chris McKay at NASA's Ames Research Center and Eliot Young of the Southwest Research Institute to convert these images into a map of surface features.