BYU scientist leads discovery of mountains on Saturn's largest moon

By analyzing images from NASAs Cassini Radar instrument, a Brigham Young University professor helped discover and analyze mountains on Saturns largest moon, additional evidence that it has some of the most earthlike processes of any celestial body in the solar system.

Planetary scientist Jani Radebaugh is lead author of the discovery paper in the December issue of the astronomy journal Icarus. The images retrieved by the Cassini Radar are the first images showing the details of Titans surface — previous spacecraft and telescopes could not pierce the haze and clouds surrounding the moon to the surface.

The discovery of mountains on Titan grew out of Radebaughs collaboration with a research team that recently found sand dunes and methane lakes on Titan. Radebaugh was a coauthor on the Science magazine study that introduced Titans sand dunes in May 2006 as well as the Nature study that introduced Titans methane lakes in January 2007.

Since this is the first time humans have been able to see through the haze to Titans surface, it was shocking to find these mountains, channels, dunes, and cryo-lava flows, Radebaugh said. We had to wait until we got all the way to Titan to see these landforms that are so similar to Earth.

Upon receiving the images from NASA, Radebaugh, in collaboration with the Cassini Radar Team, discovered the mountains and began analyzing their characteristics. With no instrument to precisely measure the mountains height, Radebaugh looked at the light and shadows in the radar images to calculate the mountains slope and then derive their height.

According to the study, Titans mountains are most likely made of water ice and are relatively small in height, at most 2 km (1.25 mi) from base to peak. Thats about half as tall as Mount Timpanogos near BYUs campus. The consistently short height of Titans mountains provides evidence that they have been subject to similar amounts of erosion, that they are roughly the same age or that the materials are behaving in a way that prevents them from growing taller.

Dr. Radebaughs work represents an important advance in our understanding of that icy moon and the Earth, said Dr. Jason Barnes, a research scientist at the NASA Ames Research Center. Her discovery tells us about the mountain-building process in general and about Titans crust in particular.

Prior to Cassini, scientists assumed that most of the topography on Titan would be impact structures, yet these new findings reveal that similar to Earth, the mountains were formed through geological processes on the moon.