Written by DC Agle/Guy Webster
NASA’s Jet Propulsion Laboratory
Pasadena, CA – At 10:31pm PDT, April 27th, (1:31pm EDT), NASA’s Mars Science Laboratory, carrying the one-ton Curiosity rover, will be within 100 days from its appointment with the Martian surface.
At that moment, the mission has about 119 million miles (191 million kilometers) to go and is closing at a speed of 13,000 mph (21,000 kilometers per hour).

On Sunday, April 22nd, a week-long operational readiness test concluded at JPL. The test simulated aspects of the mission’s early surface operations. Mission planners and engineers sent some of the same commands they will send to the real Curiosity rover on the surface of Mars to a test rover used at JPL.
“Our test rover has a central computer identical to Curiosity’s currently on its way to Mars,” said Eric Aguilar, the mission’s engineering test lead at JPL. “We ran all our commands through it and watched to make sure it drove, took pictures and collected samples as expected by the mission planners. It was a great test and gave us a lot of confidence moving forward.”
The Mars Science Laboratory spacecraft, launched November 26th, 2011, will deliver Curiosity to the surface of Mars on the evening of August 5th, 2012, PDT (early on August 6th, Universal Time and EDT) to begin a two-year prime mission. Curiosity’s landing site is near the base of a mountain inside Gale Crater, near the Martian equator. Researchers plan to use Curiosity to study layers in the mountain that hold evidence about wet environments of early Mars.
JPL, a division of the California Institute of Technology in Pasadena, manages the mission for the NASA Science Mission Directorate, Washington. More information about Curiosity is online at http://www.nasa.gov/msl and http://mars.jpl.nasa.gov/msl/ .
You can follow the mission on Facebook at: http://www.facebook.com/marscuriosity and on Twitter at: http://www.twitter.com/marscuriosity .