MARS: Modeled after the spy satellites used to keep an eye on Earth, NASA's Global Surveyor will from Thursday be able to spot objects less than two meters long, as it starts its multi-year polar orbit miles above Mars. TIME science writer Jeffrey Kluger reports that the probe - designed in part to pick up where the ill-fated Mars Observer left off when it lost contact with Earth four years ago - will help future missions by mapping Mars more extensively than ever before. "But, more importantly," Kluger adds, "it's going to map it from a polar orbit instead of a waistline orbit as is customarily done." How come? For starters, such an orbit will map areas passed over by prior missions. More importantly, it will allow for close ups of the planet's polar ice caps, scoping out possible hiding places for past or present life forms.
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