Titan

Despite centuries of speculation and decades of research, scientists are still seeking fundamental clues to the question of how life began on Earth. Titan [TIE-tun] is the frozen vault that may contain these secrets for the Cassini-Huygens mission to discover.

Titan is the largest of Saturn's moons, bigger than the planets Mercury and Pluto. The study of Titan is one of the major goals of the Cassini-Huygens mission because it may preserve, in deep-freeze, many of the chemical compounds that preceded life on Earth.

Long hidden behind a thick veil of haze, Titan is the only moon in the solar system that possesses a dense atmosphere (10 times denser than Earth's). The fact that this atmosphere is rich in organic material and that living organisms as we know them are composed of organic material is particularly intriguing. "Organic" means only that the material is carbon-based, and does not necessarily imply any connection to living organisms.

The story of Titan is gradually unfolding. Titan is a dynamic place with complex geologic processes. The lack of many craters indicates that Titan's surface may be relatively young, because Earth-like processes of tectonics, erosion, winds, and perhaps volcanism, shape its surface. Though hazy, Titan's atmosphere is relatively cloud-free.

Cassini will execute 45 flybys of Titan, some of them only several hundred kilometers from its surface. The European Space Agency's Huygens probe, which pierced Titan's thick-dense haze, was dedicated to the study of Titan's atmosphere. The probe actually survived for several hours on the surface and returned stunning images.

Credit: NASA/JPL/Space Science Institute

Source: NASA