Mar 21 2008
From The Space Library
A team of researchers led by Ralph D. Lorenz of Johns Hopkins University’s APL announced in the journal Science that NASA’s ESA spacecraft had discovered evidence of an underground ocean composed of water and ammonia on Saturn’s moon Titan. During 19 flybys made between October 2005 and May 2007, ESA’s SAR had gathered images of the moon’s surface that showed that distinct features on Titan’s surface, such as lakes, canyons, and mountains, had shifted location over time by as much as 19 miles (31 kilometers). The scientists believed that this shifting had occurred because winds in Titan’s heavy atmosphere had moved the moon’s thin surface crust, which was separated from the moon’s core by an ocean, measuring 60-120 miles (97-193 kilometers) deep. Scientists had previously discovered evidence of underground oceans on other moons in Earth’s solar system. However, the researchers were particularly interested to discover the presence of liquid water on Titan, because that moon has many of the same organic compounds as Earth.
NASA, “ESA Spacecraft Finds Ocean May Exist Beneath Titan’s Crust,” news release 08-085, 20 March 2008, http://www.nasa.gov/home/hqnews/2008/mar/HQ_08085_cassini_ocean.html (accessed 2 February 2011); Charles Q. Choi, “Evidence for Ocean Found at Saturn’s Moon Titan,” Space.com, 20 March 2008, http://www.space.com/5151-evidence-ocean-saturn-moon-titan.html (accessed 3 February 2011); Ralph D. Lorenz et al., “Titan’s Rotation Reveals an Internal Ocean and Changing Zonal Winds,” Science 319, no. 5870 (21 March 2008): 1649-1651.
Researchers led by Mikki M. Osterloo of the University of Hawaii announced in the journal Science that their team had found evidence of salt deposits on the surface of Mars. The scientists explained that the existence of salt deposits would provide evidence that Mars had once had an abundant supply of near-surface water, which could have sustained life. NASA’s Mars Odyssey Thermal Emission Imaging System, a camera capable of producing images in visible light and infrared wavelengths, had made the discovery. The images showed spectral features consistent with chloride minerals, located at approximately 200 sites in the southern hemisphere. The salt deposits ranged in size from 0.5 square miles (1.3 square kilometers) to 25 times that size, with a thickness ranging from 3 to 10 feet (0.9 to 3 meters). Scientists believed that the mineral sites, which were approximately 3.5 to 3.9 billion years old, had formed when groundwater seeped to the surface and evaporated, leaving behind salty deposits.
NASA, “NASA Mission Finds New Clues To Guide the Search for Life on Mars,” news release 08-084, 20 March 2008, http://www.nasa.gov/home/hqnews/2008/mar/HQ_08084_Mars_Deposits.html (accessed 13 January 2011); David Mosher, “Newly Found Martian Salt Deposits Suggest Ancient Life,” Space.com, 20 March 2008, http://www.space.com/5150-newly-martian-salt-deposits-suggest-ancient-life.html (accessed 13 January 2011); M. M. Osterloo et al., “Chloride-Bearing Materials in the Southern Highlands of Mars,” Science 319, no. 5870 (21 March 2008): 1651-1654.
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