NASA Mars Opportunity: MRO restarts hunt for habitable sites

Opportunity rover’s 1st mountain climbing goal is dead ahead in this up close view of Solander Point at Endeavour Crater. 

Opportunity will ascend the mountain looking for clues indicative of a Martian habitable environment. 

This navcam panoramic mosaic was assembled from raw images taken on Sol 3385 (Aug 2, 2013). 

Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Ken Kremer (kenkremer.com)

MRO, NASA's most powerful Mars orbiter has been given the green light today (Aug. 5) to capture new high resolution spectral scans that are absolutely crucial for directing the long lived Opportunity rover's hunt for signatures of habitability atop the intriguing mountain she will soon ascend.

In a plan only recently approved by NASA, engineers are aiming the CRISM mineral mapping spectrometer aboard the Mars Reconnaissance Orbiter (MRO) circling overhead to collect high resolution survey scans of Solander Point – Opportunity's 1st mountain climbing goal along the rim of huge Endeavour Crater.

"New CRISM observations centered over Solander Point will be acquired on Aug. 5, 2013," Ray Arvidson told reporters.

Arvidson is the mission's deputy principal scientific investigator from Washington University in St. Louis, Mo. NASA's decade old rover Opportunity is about to make 'landfall' at the base of Solander Point, the Martian mountain she will scale in search of the chemical ingredients that could sustain Martian microbes.

So the new spectral data can't come back to Earth soon enough, and all this is taking place as NASA's Curiosity rover celebrates her 1st Birthday on the Red Planet. .

Currently, the science team lacks the same quality of high resolution CRISM data from Solander Point that they had at a prior stop at Cape York and that data was crucial because it allowed the rover to be precisely targeted – and thereby discover a habitable zone, Arvidson stated.

"CRISM collected lots of overlapping measurements at Cape York to sharpen the image resolution to 5 meters per pixel to find the phyllosilicate smectite [clay minerals] signatures at Matejivic Hill on Cape York."

"We don't have that at Solander Point. We only have 18 meters per pixel data. And at that resolution you can't tell if the phyllosilicate smectite [clay minerals] outcrops are present."

Today's new survey from Mars orbit will vastly improve the spectral resolution – from 18 meters per pixel down to 5 meters per pixel.

"5 meter per pixel CRISM resolution is expected in the along-track direction over Solander Point by commanding the gimbaled optical system to oversample that much," Arvidson explained.

Opportunity rover’s view from very near the foothills of Solander Point looking along the rim and vast expanse of Endeavour Crater.

Solander Point is the 1st Martian Mountain NASA’s Opportunity will climb and the rovers next destination.

Solander Point may harbor clay minerals indicative of a past Martian habitable environment. This navcam mosaic was assembled from raw images taken on Sol 3374 (July 21, 2013).

Credit: NASA/JPL/Cornell/Marco Di Lorenzo/Ken Kremer (kenkremer.com)

The new CRISM spectral survey from Mars is essential to enable the science team to carefully study the alien, unexplored terrain in detail and locate the clay minerals and other water bearing minerals, even before the rover arrives.

Clay minerals form in neutral pH water conducive to life.

But it took some cajoling and inter team negotiations to convince everyone to move forward with the special but crucial CRISM imaging plan.

Since MRO is getting on in age – it launched in 2005 – NASA and the spacecraft managers have to carefully consider special requests such as this one which involves slewing the MRO spacecraft instruments and therefore entails some health risks to the vehicle.

"CRISM has been operating at Mars since 2006 and sometimes the optics on a gimble have actuators that get stuck a little bit and don't sweep as fully as planned."

Nevertheless, Arvidson told me a few weeks ago he was hopeful to get approval.

U.S. restarts Plutonium 238 production for space probes

A glowing red hot pellet of plutonium-238 dioxide to be used in a radioisotope thermoelectric generator for space missions.

The Department of Energy has produced its first batch of non-weapons grade plutonium, used to power space probes, since a nuclear reactor shutdown 25 years ago, NASA officials said on Monday.

The U.S. space agency turned to buying radioactive plutonium-238 from Russia after safety issues prompted the Department of Energy to close its Savannah River Site in South Carolina in the late 1980s.

The Russian supply line ended in 2010, leaving NASA with a small and aged supply of plutonium for space probes flying missions that are ill-suited for solar power.

Plutonium naturally radiates heat, which can be converted into electricity by a device called a radioisotope thermo-electric generator.

NASA has been flying nuclear-powered probes since the 1970s. Ongoing missions using such probes include the Mars rover Curiosity, the Saturn-orbiting Cassini spacecraft, Pluto-bound New Horizons and the twin Voyager probes, which are leaving the solar system.

"The new plutonium is very important to us," Jim Green, the head of NASA's planetary science division, said during a briefing at a Lunar and Planetary Science Conference in Houston.

In partnership with NASA, the Department of Energy irradiated the radioactive metal neptunium-237 with neutrons at the Oak Ridge National Laboratory in Tennessee for about a month and successfully produced a small amount plutonium.

"This is just a test," Green said, adding that a report from the Energy Department on production plans and costs should be finished before the end of the year.

NASA is looking for the department to produce about 3.3 to 4.4 pounds (1.5 to 2 kg) of plutonium-238 per year.

Newly made plutonium has the added benefit of reviving older plutonium that has decayed past the point of being viable for deep space probes.

"The new material when we add with our old plutonium, which is more than 20 years old in some cases, really allows us to get the appropriate energy density out," Green said.

NASA also has been working on a more energy efficient generator, called the Advanced Stirling Radioisotope Generator, which can produce four times more electrical power per kilogram of plutonium-238.

Green said two such flight-ready generators are on schedule for completion in 2016. Neither has yet been assigned for a specific mission.