Sept. 22, 2006 — It's been a long, slow haul, with many stops to explore and a few unplanned breaks due to equipment glitches, but a robotic Mars scout is about to reach paydirt.
The place is called Victoria Crater, and like most of Mars doesn't look like much at first blush: a big hole in the ground, about a half-mile wide and 230 feet or so deep.
But scientists catching a glimpse of Victoria from the Mars Global Surveyor, an orbiting reconnaissance spacecraft, have seen enough to devote the rover, named Opportunity, to what will likely be its final resting place.
"This has been the destination ever since Opportunity left Endurance Crater more than 18 months ago," said NASA's Guy Webster, a spokesman at the Jet Propulsion Laboratory in Pasadena,
Calif., which manages the program.
Victoria's walls are layered with exposed rock, a stack of geologic history measuring more than 100 feet thick.
Opportunity Lands
By deciphering rock and soil content and structure at Opportunity's initial landing spot, Eagle Crater, scientists came up with the first direct evidence of a shallow, ancient ocean
on Mars.
The search for water has been NASA's holy grail in its ongoing quest to learn if life ever arose on Mars.
One of the biggest questions left unanswered by the findings at Eagle was if the water had been around long enough for life to form. Scientists had hoped for more answers at the rover's next
stop, Endurance Crater, where it spent nine months exploring a stack of exposed rocks 23 feet thick.
From there, Opportunity set out for Victoria, stopping along the way to study rocks and soils which together told a story of shallow
lakes, shifting dunes and variable levels of groundwater — all very acidic.
It is at Victoria that scientists have their best shot, at least during this ground foray of Mars, to fill in some of the missing history.
"Eagle Crater is about the size of your garage. It's just a tiny little hole in the ground, and yet at the same time we were very excited to see layers of rock that were about a foot thick," said rover science team member John Grotzinger, with the California Institute of Technology in Pasadena.
The next stop, Endurance Crater, was about the size of
baseball park, Grotzinger explained, with rock layers several feet thick.
