PASADENA, Calif., July 19 (UPI) -- The Mars rover Spirit is being steered in reverse because of a sticky front wheel, NASA engineers said Monday.
The engineers have decided not to use the problem right-front wheel except where it is absolutely essential, such as driving up the sandy slopes of the Columbia Hills, which Spirit is currently exploring.
Engineers discovered the malfunction because the wheel was drawing roughly twice the electric current of the other five and attempts to improve its performance have only been partially successful. Efforts to warm and rotate the wheel to distribute lubrication had yielded a 25-percent increase in performance, NASA said.
Spirit appears to have found its first outcrop of layered rocks on Mars, but so far mission scientists have been unable to determine whether they are layered due to the action of water, wind or volcanoes.
Spirit, which landed in a region of Mars called Gusev Crater in early January, has been operating more than twice as long as NASA controllers originally expected.
