NASA Tweaks Curiosity's Course To Mars

NASA's Mars Science Laboratory successfully completed a series of highly choreographed interplanetary maneuvers tonight -- engine firings that refined its course toward the red planet.

Eight precisely timed ignitions that spanned almost three hours -- 175 minutes -- were completed successfully. Combined, the eight Trajectory Correction Maneuvers represented the largest change-of-course the Mars Science Laboratory and its Curiosity rover will make on the way to an August arrival.

"We've completed a big step toward our encounter with Mars," Brian Portock of NASA's Jet Propulsion Laboratory, Pasadena, Calif., deputy mission manager for the cruise phase of the mission, said in a statement. "The telemetry from the spacecraft and the Doppler data show that the maneuver was completed as planned."

Launched Nov. 26 aboard a United Launch Alliance Atlas V rocket, the Mars Science Lab is scheduled to land at a region called Gale Crater between 1 a.m. and 1:30 a.m. EDT Aug. 6. The spacecraft by then will have made a looping, 354-million-mile journey to get there.

Once on the ground, the Curiosity rover will use science instruments to determine whether Gale Crater could ever have been a place hospitable to primitive life. Any subsequent discovery of microbes on Mars would prove life existed elsewhere in the universe.

The three-hour series of thruster firings began at 6:10 p.m. EST and accomplished a significant goal. The vehicle was launched on a trajectory that would have missed the planet by tens of thousands of miles. But that was done by design. NASA wanted to make sure the upper stage of the Atlas V rocket that launch the lab would miss Mars by a wide margin rather than crash into its surface, potentially contaminating it with microbes from Earth. The Centaur upper stage did not go through the planetary protection measures that the lab did prior to launch.

So the Centaur will fly by Mars, and NASA has five more opportunities to tweak the trajectory of the Mars Science Lab and its Curiosity rover.

The next will come on March 26.