火星探路者
The U.S. "Mars Pathfinder" was launched in December 1996 and released the first acting rover on Mars, named "Sojourner", in July 1997. It failed in September 1997, probably due to electronics failure caused by the cold temperatures. "Mars Pathfinder" was part of the canceled Mars Environmental Survey program with a set of 16 landers planned for 1999–2009.