An anonymous reader writes "'Jade Rabbit,' the first lunar rover successfully deployed by China, has now been officially declared 'lost.' The rover encountered problems on January 25th, just over a month into its planned three-month mission. 'The rover's mechanical problems are likely related to critical components that must be protected during the cold lunar night. When temperatures plunge, the rover's mast is designed to fold down to protect delicate instruments, which can then be kept warm by a radioactive heat source. Yutu also needs to angle a solar panel towards the point where the sun will rise to maintain power levels. A mechanical fault in these systems could leave the rover fatally exposed to the dark and bitter cold.'"