Can China's Jade Rabbit bounce back?
27 January 2014 Last updated at 19:55 GMT
China's moon rover, Jade Rabbit, is in trouble after experiencing what is described as a "mechanical control abnormality".
The exploration vehicle landed in December and was expected to operate for around three months.
State media are reporting that scientists are organising repairs but little is known about the malfunction.
The BBC's Science Editor David Shukman explains what might have gone wrong.