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-- Geophysical Monitoring Station (GEMS) which would study the structure and composition of the interior of Mars and advance understanding of the formation and evolution of terrestrial planets;
-- Titan Mare Explorer (TiME) which would provide the first direct exploration of an ocean environment beyond Earth by landing in, and floating on, a large methane-ethane sea on Saturn's moon Titan; and
-- Comet Hopper which would study cometary evolution by landing on a comet multiple times and observing its changes as it interacts with the sun.
"This is high science return at a price that's right," said Jim Green, director of NASA's Planetary Science Division in Washington. "The selected studies clearly demonstrate a new era with missions that all touch their targets to perform unique and exciting science."
The three selected technology development proposals will expand the ability to catalog near-Earth objects, or NEOs; enhance the capability to determine the composition of comet ices; and validate a new method to reveal the population of objects in the poorly understood, far-distant part of our solar system, JPL said.