Spectacular new images of a gorgeous gaping hole on Mars are streaming back to Earth from NASA’s Opportunity Mars Rover. So let’s take a 3 D stroll placing all of us at Santa Maria Crater – “On Mars”. Via the photo mosaics above and below, we will circle in three dimensions about the stunningly beautiful Santa Maria Crater. At the southeast portion of the rim, the crater also possesses a scientific goldmine of hydrated mineral deposits. These minerals are indicative of the past flow of liquid water on Mars, an essential requirement for the formation of life.
Opportunity made landfall at the western edge of Santa Maria on Dec. 15 (Sol 2450) after a long and arduous journey of some 19 km since departing from Victoria Crater over 2 years ago in September 2008. She crawled closer to the rim the next day on Dec. 16 (Sol 2451) unveiling a magnificent vista of jumbled ejecta rocks, steep sloped cliffs and undulating sand dunes across the crater floor.
“Santa Maria is a relatively fresh impact crater. It’s geologically very young, hardly eroded at all, and hard to date quantitatively. On the order of 10 million years old or less,” said Ray Arvidson in an interview from Washington University in St. Louis. Arvidson is the deputy principal investigator for the Spirit and Opportunity rovers.
“Santa Maria is the freshest big guy that Opportunity has seen and has a raised rim,” Arvidson told me. “It is much younger than Endurance Crater which Opportunity visited a few months after landing on Mars way back in 2004 and is roughly the same diameter.” See the entire Opportunity traverse map below.
“The crater is young enough that the interesting hydrate outcrops may not be coated with the nanophase iron oxide dust. There is virtually no erosion. We can see the ejecta rays and blocks,“ said Arvidson.
While sitting just five meters from the rim on Dec. 16, Opportunity imaged the football field sized crater – some 90 m wide – with both its left and right eye navigation cameras. A mosaic of these images was stitched together by NASA to create a stunning 360 degree stereo panoramic vista. The images are snapped from the same height seen by an adult to give the perspective that a human eye would see when standing “On Mars”.
The crater is the centerpiece of the stereo image above, which shows the crater’s sharp rim and rocks ejected from the impact that had excavated the crater. You will need to whip out your red-cyan stereo glasses to experience the full three-dimensional effect of the scene. Be sure to wear the red lens on the left, and try not to fall off the cliff.
Click here for the entire 360-degree high resolution stereo view – its 10 MB in all. South is at the center. North is at both ends. The view is presented as a cylindrical-perspective projection. The wheel tracks left behind in the Martian dirt – as the rover approached the crater – are seen at the far right and are also highlighted in our 2 D mosaic below.
Off in the distance, several portions of the rim of Endeavour Crater are visible as bumps on the horizon. Endeavour is the ultimate target of Opportunity’s long term trek across the Martian dunes at the Meridiani Planum region and is some 22 kilometers in diameter.
“Endeavour shows significant signatures of phylloslicates, or clay minerals, and water bearing sulfate minerals which formed in the presence of liquid water,” Arvidson explained. “The phyllosilicates formed at the crater rim about 3.8 to 4.2 Billion years ago and predate the sedimentary rocks which are younger than 3.8 billion years.”
Pictured below is a collection of stereo photo mosaics for a North to South up close tour around the rim of Santa Maria. Several of the images were created by members of unmannedspaceflight.com.
“Opportunity will drive in a counterclockwise direction around Santa Maria to reach the very interesting hydrated sulfates on the other side. We’ll make 3 stops or more depending on what we see”
“On Dec. 19 (Sol 2454) we bumped the vehicle even closer to the rim from the initial approach point, to a promontory we’ve nicknamed ‘Palos’, stated Arvidson. “Opportunity was a mere 2.5 meters from the edge. At ‘Palos’, the rover collected the first set of long baseline, high resolution stereo images for creating a 3 D digital elevation map.”
“The coves at Santa Maria will be named after the islands which Columbus visited, using the native American language. All the rocks and boulders strewn about will be named after the sailors on the voyage with Columbus,” explained Arvidson.
“This past weekend we drove about 20 meters southeast towards the second location named ‘Wanahani’. On Tuesday of this week (Dec. 28) we bumped to the edge. The plan is to photograph the ejecta rocks and collect the next set of long baseline, high resolution stereo images.”
The third stop – which must be reached before Solar Conjunction in mid January 2011- will take Opportunity to the science hot spot detected by the powerful CRISM mineral mapping spectrometer circling above Mars aboard NASA’s Mars Reconnaissance Orbiter (MRO).
“With CRISM we are trying to cover all the rim segments to better understand the nature and geologic setting of the iron and magnesium smectite clay mineral exposures. The southeast portion of Santa Maria is generally the location of the CRISM spectra that show hydrated sulfates. Opportunity will go to the southeast rim and try and find a nice outcrop on the rim side to do measurements to field verify the expected mineralogy,” explained Arvidson.
“We might do a toe dip with the wheels but there is no plan to go inside.”
“We will use the Rock Abrasion Tool (RAT) to drill into a selected target. That spot will be named after ‘Columbus’.
The exposures of hydrated sulfates have a bright toned appearence in the images.
“With the sun over the camera’s shoulder there is a phenomenon called opposition effect in which rocks and soils become particularly bright when the sun-camera-surface line up, Arvidson told me. “But, it also may be that the bright looking rocks are intrinsically bright and not coated with the nanophase iron oxide coatings we have seen on previous outcrops. All in the realm of testable working hypotheses.”
“On Dec. 30 we are planning another CRISM spectral mapping campaign with MRO over Santa Maria,” said Arvidson. “Using a new technique which gimbals, or swivels, the CRISM optics we hope to use a pixel overlap technique to improve the ground resolution from 18 meters across to 6 meters across. This data will be used in tactical decisions about where to drive on Mars.”
Read more of my interview with Ray Arvidson in the next feature story describing the exciting plan for science exploration at Santa Maria and Endeavour, the outlook for Spirit and more – along with new mosaics from “Wanahani”.