PLANETARY MISSION UPDATES
|MRO Views Four Martian Avalanches
On February 19, 2008, the high-resolution imager HiRISE aboard the Mars Reconnaissance Orbiter captured an amazing view of at least four Martian avalanches in action. They occurred along the red planet's north polar scarp, an impressive cliff over 700 meters (2300 feet) tall and capped with carbon dioxide frost. The image provides a closer look at one of the avalanches. The clouds of dust trace the path of the fallen debris.
Image courtesy of NASA/Jet Propulsion Laboratory-Caltech/University of Arizona
|Lakes on Titan
The false-color image (top left) was created using radar data acquired by Cassini during a flyby of Saturn's moon Titan. The irregularly shaped areas (shades of blue) appear to be lakes filled with either liquid hydrocarbon methane and/or ethane. According to new data, Titan has hundreds of times more liquid hydrocarbons than all of the known oil and natural gas reserves on Earth. Like water on Earth, these organic compounds seem to rain down from the sky. Having mapped about 20 percent of the moon's surface, Cassini has already discovered several hundred lakes and seas. The artist's concept (bottom left) reveals how a hydrocarbon lake might appear to an observer on Titan.
Image courtesy of NASA/JPL/SSI & Artist's Concept courtesy of Steven Hobbs (Brisbane, Queensland, Australia)
|Enceladus' Plumes and Tiger Stripes
During its recent March flyby of Saturn's moon Enceladus, the Cassini spacecraft took a closer look at the geyser-like plumes erupting from the moon's south polar region. Analysis of the plume material revealed organic compounds, water vapor and volatile gases. The composition is very similar to that of comets.
The plumes originate from giant fissures, called tiger stripes. Internal heat and various compounds escape through the fissures, warming the surface and causing the surrounding ice to evaporate. The heat map (inset) reveals temperature data collected during the flyby. Compared to the rest of the icy moon, the tiger stripes are warmer by at least 93 °C (63 °F). The plumes are located at the warmest spots (yellow areas) along the fissures.
Image courtesy of NASA/JPL/SSI and Heat Map courtesy of NASA/JPL/GSFC/SwRI/SSI
Former What's New Topics:
©2002 National Air and Space Museum