Mars Pathfinder

*Mars Pathfinder*
	Pathfinder and Sojourner at JPL in October 1996, being 'folded' into its launch position.
Mission type	Lander · Rover
Operator	NASA · Jet Propulsion Laboratory
COSPAR ID	1996-068A
SATCAT no.	24667
Website	mars.nasa.gov/MPF/
Mission duration	85 days; Launch to last contact: 9 months, 23 days
Spacecraft properties
Launch mass	890 kg (includes propellant)
Power	Pathfinder: 35 W; Sojourner: 13 W
Start of mission
Launch date	December 4, 1996 06:58:07 UTC
Rocket	Delta II 7925 (#D240)
Launch site	Cape Canaveral SLC-17
Contractor	None
End of mission
Last contact	September 27, 1997 10:23 UTC
Mars lander
Landing date	July 4, 1997 16:56:55 UTC ; MSD 43905 04:41 AMT
Landing site	Ares Vallis, Chryse Planitia, Mars; 19°5′50″N 33°15′14″W / 19.09722°N 33.25389°W
Transponders
Band	X-Band with high-gain antenna
Bandwidth	6 kb/s to 70 m Deep Space Network, 250 b/s to surface command
	; Official insignia of the Mars Pathfinder mission. Discovery program

Mars Pathfinder was an American robotic spacecraft that landed a base station with a roving probe on Mars in 1997. It consisted of a lander, renamed the Carl Sagan Memorial Station, and a lightweight, 10.6 kg (23 lb) wheeled robotic Mars rover named Sojourner, the first rover to operate outside the Earth–Moon system. The mission terminated in 1998.

Launched on December 4, 1996, by NASA aboard a Delta II booster a month after the Mars Global Surveyor, it landed on July 4, 1997, on Mars's Ares Vallis. The region is called Chryse Planitia, a part of the Oxia Palus quadrangle. The lander carried a series of scientific instruments to analyze the Martian atmosphere, climate, and geology. Analysis of the rocks and soil was a key objective. It was the second project from NASA's Discovery Program, which promotes the use of low-cost spacecraft and frequent launches under the "cheaper, faster, and better" motto promoted by then-administrator Daniel Goldin. The mission was directed by the Jet Propulsion Laboratory (JPL), a division of the California Institute of Technology, responsible for NASA's Mars Exploration Program. The project manager was JPL's Tony Spear.

This mission was the first of a series of missions to Mars that included rovers, and was the first successful lander since the two Vikings landed on Mars in 1976. Although the Soviet Union successfully sent rovers to the Moon as part of the Lunokhod program in the 1970s, its attempts to use rovers in its Mars program failed.