Astronomers have generated the first complete full-color map of the surface of Saturn's largest moon, Titan - a frozen place where liquid methane rains from the sky, and where scientists analyzing the images have discovered an astounding range of Earth-like characteristics.

Scientists at the French University of Nantes generated the map using pictures taken by NASA's robotic Cassini spacecraft, which has voyaged around Saturn for over six years, during its first 70 flybys of Titan. Cassini's Visual and Infrared Mapping Spectrometer, or VIMS, is equipped with the ability to pierce through Titan's opaque atmosphere and methane clouds, like a window to its multifarious terrain.

After carefully combining images that were transmitted over six years by a NASA spacecraft circling Saturn, scientists have generated a complete surface map of the biggest moon around Saturn, Titan, that reveals a variety of unexpected Earth-like features in the terrain.

Space researchers are keenly interested in Titan because of its sand dunes, mountains, valleys and lakes, and its puzzling atmosphere. Titan is a land of hydrocarbons, such as the methane that most researchers believe rains down on Titan's surface, collects in lakes and forms clouds.

The Cassini spacecraft was completed in 1997 and is expected to make dozens more approaches to Titan before the end of its orbital mission at Saturn in 2017.

The group of scientists needed to perform painstaking pixel-by-pixel analyses of every image because the observations of Titan over six years were made from different distances. The drudging activity necessitated the analysts to resize the images to the same scale, as well as compensate for variance in light and contrast, and compensate for atmospheric distortions.

With its dazzling rings and 60 moons, Saturn is more than 1. 2 billion kilometers (700 million miles) in distance from the Earth's orbit.