In a rare setback to its ambitious space programme, China may not be able to repair the country's first lunar rover which has broken down on the surface of the moon.
"Masters are working round the clock. In spite of that, I know I might not be able to make it through this lunar night," a "report" from the lunar rover to ground control said.
"If this journey is to be suspended ahead of schedule, I am not fearful. No matter whether I can be fixed or not, I believe I have left masters much valuable information and experience," the report was quoted as saying by the South China Morning Post.
The report written as if it was by the rover 'Jade Rabbit' or 'Yutu' in Chinese, itself noted that half of the 130 moon missions had encountered failures in some form.
"I am not that sad. Like all the heroes in other stories, I have just encountered some problems in my adventure," the report said.
Last week 'Yutu' experienced a mechanical control abnormality due to "complicated lunar surface environment".
The abnormality emerged before the rover entered its second dormancy at dawn on Saturday as the lunar night fell, the State Administration of Science, Technology and Industry for National Defence (SASTIND) said.
The lander, another part of the Chang'e-3 probe, also "fell asleep" earlier on Friday.
The pair went dormant for two weeks about one month ago when the first lunar night of the mission occurred.
One night on the Moon is about 14 days on Earth during which the temperature falls below minus 180 degrees Celsius.
During the lunar night, there is no sunlight to provide power to Yutu's solar panel.
Beijing-based writer Zhang Yian was quoted as saying: "This is too heavy a burden. If the rabbit cannot stand again, maybe we should let it have a rest."
Jade Rabbit was originally scheduled to carry out geological surveys and astronomical observations for three months after it landed on the moon on December 14.
A state-run Xinhua report on the rover said it had travelled over 100 metres and had completed most of its tasks.
