Mars Recon Orbiter
As it nears Mars on March 10, a NASA spacecraft designed to examine the red planet in unprecedented detail from low orbit will point its main thrusters forward, then fire them to slow itself enough for Mars' gravity to grab it into orbit.
Ground controllers for Mars Reconnaissance Orbiter expect a signal shortly after 1:24 p.m. Pacific time (4:24 p.m. Eastern time) that this mission-critical engine burn has begun. However, the burn will end during a suspenseful half hour with the spacecraft behind Mars and out of radio contact.
The orbiter carries six instruments for studying every level of Mars from underground layers to the top of the atmosphere. Among them, the most powerful telescopic camera ever sent to a foreign planet will reveal rocks the size of a small desk. An advanced mineral-mapper will be able to identify water-related deposits in areas as small as a baseball infield. Radar will probe for buried ice and water. A weather camera will monitor the entire planet daily. An infrared sounder will monitor atmospheric temperatures and the movement of water vapor.
The instruments will produce torrents of data. The orbiter can pour data to Earth at about 10 times the rate of any previous Mars mission, using a dish antenna 3 meters (10 feet) in diameter and a transmitter powered by 9.5 square meters (102 square feet) of solar cells.