15 October 2008
Data from Rovers, Spacecraft Set Stage for More Mars Exploration
Mars Science Laboratory scheduled for 2009 launch despite rising costs
Washington — Hundreds of millions of kilometers from Earth, at a red planet that is the focus of much scientific attention, a spacecraft’s mission has been extended into 2010, two rovers are working long past their primary missions, and a landing site is being chosen for the most capable mobile robot yet to visit Mars.
The Mars Science Laboratory (MSL), a $1.6 billion advanced rover that is larger and can travel farther than Spirit and Opportunity, the rovers NASA sent to explore Mars in 2004, is in development for a launch opportunity in September-October 2009.
Despite “incredible technical progress” during three years of development, Doug McCuistion, director of NASA’s Mars Exploration Program, said in an October 10 briefing that delays in delivery of some of the spacecraft’s hardware and software have increased the MSL’s projected cost by $300 million to $1.9 billion.
After an October 10 meeting with NASA Administrator Michael Griffin, the third scheduled in 2008 to review MSL progress and status, McCuistion announced that NASA would “continue unabated toward the launch in 2009.”
The main problem is a delay in the delivery of small motors called actuators that are used in the wrist and elbow joints of the robotic arm, wheels, sample-handling systems and several other applications.
“Because of the mass of MSL and its size,” McCuistion said, “those are reasonably complex motors and they are difficult to produce.”
NASA expects all the actuators to be delivered by the end of November or early December, he said, in time to build and install the devices in advance of tests scheduled for spring 2009.
The next MSL assessment meeting with Griffin will be held in early January 2009. If the MSL misses its 2009 launch window, the next window will be 26 months later, in 2011.
“It is easy to say let’s just cancel it and move on, but we have poured over a billion-and-a-half dollars into this,” said Ed Weiler, associate administrator for NASA’s Science Mission Directorate. “The science is critical. It is a flagship mission in the Mars program, and as long as we think we have a good technical chance to make it, we’re going to do what we have to do.”
The powerful cameras and spectrographic instruments of another spacecraft, the Mars Reconnaissance Orbiter, are collecting data to help scientists evaluate each potential landing site. Final site selection is planned for June 2009.
MARS ODYSSEY
On October 9, NASA extended through September 2010 the mission of Mars Odyssey, the longest serving of six spacecraft now studying the Red Planet. Named after the 1968 movie 2001: A Space Odyssey, the orbiter reached Mars in 2001 and finished its prime mission in 2004.
Its goals were to detect health hazards for future human space explorers, learn about the composition of Mars and find buried water ice in the planet’s shallow subsurface.
For its extended mission, Odyssey is changing its orbit to gain better sensitivity for its infrared mapping of Martian minerals and will point its camera with more flexibility than it has ever used before.
On commands from the operations team at NASA’s Jet Propulsion Laboratory in California and Lockheed Martin Space Systems in Colorado, Odyssey fired thrusters for nearly six minutes on September 30, the final day of the mission's second two-year extension.
Increased sensitivity for identifying surface minerals is a key science goal for the mission extension. The Odyssey team will also begin occasionally aiming the camera away from the straight-down pointing in use during the mission. This will let the team fill in some gaps in earlier mapping and create some stereo, three-dimensional imaging.
Odyssey will continue providing crucial support for Mars surface missions and conducting its own investigations. It has relayed to Earth nearly all data returned from the rovers Spirit and Opportunity, and it shares with NASA's Mars Reconnaissance Orbiter the relay role for Phoenix. (See “NASA Extends Phoenix Mission as Snow Falls on Martian Plains.”)
SPIRIT AND OPPORTUNITY
NASA's twin robot geologists landed in January 2004 on opposite sides of Mars on 90-day missions to find answers about the history of water on Mars. Today, five years after the mission began, the rovers are showing some signs of age but their missions have been extended, possibly through 2009.
Opportunity returned dramatic evidence that its area of Mars stayed wet for an extended period long ago, with conditions that could have been suitable for sustaining microbial life. Spirit found evidence in its region that water in some form has changed the mineral composition of some soils and rocks.
Opportunity analyzed a series of exposed rock layers that recorded how environmental conditions changed during the times when the layers were deposited and later modified — wind-blown dunes appeared and disappeared, and the water table fluctuated.
Spirit recorded dust devils forming and moving. The images were made into movie clips, providing new insight into the interaction of Mars' atmosphere and surface. Both rovers have found metallic meteorites. Opportunity discovered one rock with a composition similar to a meteorite that reached Earth from Mars.
Most recently, Opportunity continued traveling south around the rim of Victoria Crater, stopping to take photos along the way. Opportunity also studied the atmosphere, searched for Martian clouds and scanned its own external dust-collection magnets.
Spirit is about to begin communicating with engineers on Earth more often because its energy levels, depleted during the Martian winter, are gradually rising. Spirit stays in touch by transmitting data to NASA's Odyssey orbiter, and Odyssey sends it to Earth.
More information about the Mars Science Laboratory, the Mars Exploration Rover Mission and Mars Odyssey is available at the NASA Web site.
