Cassini on EARTH Magazine

New map of Titan shows moon's hidden surface

Tue, 10 Apr 2018 12:01:33 -0400

Images of Titan captured by NASA's Cassini spacecraft have been used to create a new global topographic map of the Saturnian moon. Credit: Corlies et al., Geophysical Research Letters, December 2017/Cornell University.

Before NASA’s Cassini mission, which ended in 2017 after 13 years orbiting Saturn, little was known about the surface of the planet’s largest moon, Titan, as most of its features lie obscured under a dense, opaque atmosphere composed mainly of nitrogen gas. However, thanks to special filters that enabled Cassini’s cameras to see through the haze, the spacecraft captured high-resolution images of about 9 percent of Titan’s surface, with 25 to 30 percent of the moon imaged in lower resolution. Researchers have now used an algorithm to interpolate the remainder of the moon’s surface and create the most complete global topographic map of Titan yet.

Heating up Enceladus' ice-covered ocean

Tue, 27 Feb 2018 13:20:21 -0500

Friction produced by tidal forces acting on Enceladus' highly fragmented, porous core could produce enough heat to sustain the moon's liquid ocean. Credit: NASA/JPL-Caltech.

Saturn’s sixth-largest moon, Enceladus, is covered by ice, but just beneath its icy surface lies an ocean of liquid water. New research suggests that this internal ocean may be maintained in a liquid state by heat generated by tidal friction within the moon’s fragmented, rocky core.

Cassini's legacy after two decades

Thu, 14 Sep 2017 18:51:59 -0400

Cassini captured this view of Saturn and its rings, about 1.4 million kilometers away from the planet, using a combination of images. Credit: NASA/JPL-Caltech/Space Science Institute.

On Sept. 15, 2017, at 4:55 a.m. PT, scientists on Earth received the last transmission from the Cassini spacecraft. It descended into Saturn’s atmosphere at 122,500 kilometers per hour, which caused it to melt, thereby ensuring that Saturn’s moons Titan and Enceladus would remain protected from possible contamination by any errant Earth microbes. Cassini scientists had considered other options for the spacecraft’s end, including leaving it to float endlessly in space or parking it in orbit around Saturn. But ultimately, they chose to have it descend into Saturn’s atmosphere after deciding the data that could be returned from the descent were more valuable than any further data it might obtain by remaining in space. Scientists will make discoveries from these data for decades to come.