Mars 'crime scene' photo places rover Curiosity right where it wants to be

They call it "the crime scene" – an overhead shot of the Mars rover Curiosity's landing site, its parachute and other pieces of the rover's unique descent module strewn like so many bodies across the nearby landscape.

It was one of two fresh photos NASA unveiled Tuesday of the rover's landing area. But of the two, the overhead image, taken by the Mars Reconnaissance Orbiter (MRO), best highlights why scientists opted to send a $1.8 billion rover on a $2.5 billion, 352 million-mile mission to the bottom of a desiccated crater on the surface of Mars.

The image, which the NASA science team was poring over all night, shows Curiosity has landed in an almost ideal spot to carry out its mission.

The goal: Determine if the crater and its three-mile-high central summit could once have been hospitable to life early in Mars' history.

The mission's lead scientist, California Institute of Technology planetary scientist John Grotzinger, has noted that his team had mapped Curiosity's broader landing area in roughly half-mile-wide squares to see what interesting features they might hold as initial science targets should the rover land on one of them.

If MRO's overhead image is any indication, Curiosity won't have to travel far to begin making some noteworthy discoveries. Its explorations will begin after a several-week commissioning period.

Perhaps 200 meters or less from the rover's landing spot sits the confluence of what appear to be three geological regions, at least two of which look as though they could speak to the issue of water's presence in the impact crater at some point after it was formed some 3 billion to 4 billion years ago. Water is one of the key ingredients researchers say is necessary to support life.

The science team was studying the overhead image to see what researchers may want Curiosity to explore first.

"I don't know what the team's been talking about all night, but if it was up to me, I would go where those three [regions] come together, as a starting point," says Ken Edgett, a geologist with Malin Space Science Systems, a San Diego-based company that has built three key camera systems for Curiosity.

Dr. Edgett is the lead scientist using the Mars Hand Lens Imager, a small, focusable camera that will serve as a kind of geologist's magnifying glass to get up-close-and-personal images of some of the rocks Curiosity will analyze.

Joy Crisp, the mission's deputy project scientist, agrees that the triple junction is an intriguing spot.

The three geological deposits, as they appear in the photograph: 

• The area on which the rover sits looks like deposits set on top of sections of the other two, with an undulating leading edge reminiscent of a fan of sediment – an alluvial fan. Such deposits form when water or winds carry material down a mountain slope. Dr. Crisp notes that an alluvial fan appears north of the rover's landing site. But she adds that it's unlikely that the rover is sitting on one.

• The light patch above the heat shield's resting place is made up of a surface material identified in earlier MRO images as rock that retains a good deal of heat after sundown. Dr. Grotzinger pointed out in a briefing prior to landing that one way to form such deposits is via the presence of liquid water. But while researchers know the rock does a good job of hanging on to heat, "the irony here is that we don't know what it is," Crisp says.

• The third region, on which the heat shield rests, appears to overtop the heat-retaining rock with its own wedding-cake-like layers. 

"There's a lot to learn here about all these materials," she says.

Now that researchers know where the lander is, they hope to learn something about the rock in the lander's immediate vicinity, as well as the rock in other areas where the bits and pieces of the descent stage augered in.

Crisp notes that the dark patches around the fallen hardware represent rock deposits that in effect were dusted off during landing and impact.

In six days, MRO is slated to fly over the site again and will take color images.

"It will be kind of fun to see, when we get color," how the site has been changed by the landing, she says. Before and after images could yield clues about the nature of the rock the rover's landing exposed.