Curiosity on Track for Landing on Mars

Eight days before reaching Mars, NASA's Mars Science Laboratory spacecraft performed a flight-path adjustment scheduled more than nine months ago. The leaders of the NASA mission said that they on track for Sunday landing. The curiosity rover is the largest and most ambitious machine ever sent to another planet.

The spacecraft is on course for delivering the mission's car-size rover, Curiosity, to a landing target beside a Martian mountain at about 10:31 p.m. PDT on Aug. 5. (1:31 a.m. on Aug. 6, EDT). After landing, the rover will spend a two-year prime mission studying whether the area has ever offered environmental conditions favorable for life.

At 1,982 pounds, Curiosity is five times heavier than previous Mars rovers. On landing day, it can steer enough during its flight through the upper atmosphere to correct for missing the target entry point by a few miles and still land on the intended patch of Mars real estate. It will enter Mars at a speed of about 13,200 mph.

"The purpose of this maneuver is to move the point at which Curiosity enters the atmosphere by about 13 miles," said Tomas Martin-Mur of NASA's Jet Propulsion Laboratory, Pasadena, Calif., chief of the mission's navigation team. "The first look at telemetry and tracking data afterwards indicates the maneuver succeeded as planned."

The thruster firings altered the spacecraft's velocity by about one-fortieth of one mile per hour.

"I will not be surprised if this was our last trajectory correction maneuver," Martin Mur said of Saturday's event. "We will be monitoring the trajectory using the antennas of the Deep Space Network to be sure Curiosity is staying on the right path for a successful entry, descent and landing."

These innovations, if successful, will place a well-equipped mobile laboratory into a locale especially well-suited for its mission of discovery. The same innovations advance NASA toward capabilities needed for human missions to Mars.