A series of engine firings tonight will steer NASA's Mars Science Laboratory toward an arrival at the red planet next August, directing the spacecraft more precisely toward its Gale Crater landing site.
A highly choreographed set of eight trajectory correction maneuvers will be performed during a three-hour span that will begin about 6 p.m. EST tonight. The engine-firings represent the largest maneuvers the spacecraft will make on its 350-mile interplanetary journey.
The $2.5 billion lab and its car-sized Curiosity rover were launched Nov. 26 on a trajectory that would miss Mars by tens of thousands of miles. That was done to make sure the Centaur upper stage of its Atlas V launch vehicle would not crash into Mars, potentially contaminating the planet with microbes from Earth.
The intentionally off-course launch turned out to be so perfect that engineers passed up initial trajectory correction maneuvers that had been scheduled to take place in December.
"We are well into cruise operations, with a well-behaved spacecraft safely on its way to Mars," NASA MSL Cruise Manager Arthur Amador said in a news release. "After this trajectory correction maneuver, we expect to be very close to where we ultimately need to be for our entry point at the top of the Martian atmosphere."
Five more trajectory correction opportunities will come between now and August. The spacecraft and its rover are expected to land between 1 a.m. and 1:30 a.m. EDT Aug. 6.
The spacecraft has travelled more than 73 million miles and is moving at a speed of 9,500 mph relative to Earth and at about 69,500 mph relative to the sun.
The project is managed by NASA's Jet Propulsion Laboratory in Pasadena, Calif. More info is HERE. You can follow the mission on Facebook and on Twitter.
ABOUT THE IMAGE: The NASA photo shows the Mars Science Lab after its successful Nov. 26 deployment from a United Launch Alliance Atlas V rocket.