BEIJING -- As China celebrates the Lunar New Year, a symbol of its national pride – the unmanned lunar rover known as “Yutu,” or Jade Rabbit – sits hobbled on the dark side of the moon, possibly frozen to death.
On Dec. 14, Yutu became China’s first rover to land on the moon. The first lunar landing of any kind since an unmanned Soviet ship retrieved soil samples from the moon in 1976, it was a major triumph for the Chinese. Then last week came the bad news: The rover had experienced a “mechanical control abnormality” that may have prevented it from going into hibernation before entering the lunar night.
During the lunar night, which lasts roughly 14 Earth days, the moon’s temperature can drop to minus 180 degrees Celsius (minus 290 degrees Fahrenheit). If a rover isn’t prepared for that, experts say, it has little chance of recovering. The Chinese will know Feb. 13, when the night ends.
“It looks like the Chinese engineers have lost confidence that they will be able to get it working again,” said Joan Johnson-Freese, an aerospace specialist and professor of national security affairs at the U.S. Naval War College at Newport, R.I.
The rover, she said, was intended to operate through three lunar periods of hibernation. “Now it appears that there were mechanical difficulties before it went into this second hibernation, and if hibernation does not occur normally, the Jade Rabbit could freeze,” Johnson-Freese said in an email.
Scientists say China shouldn’t be ashamed, given that the United States and the Soviet Union suffered numerous failures before consistently executing missions to the moon. Even so, some users of social media in China sounded heartbroken when news of Yutu’s mechanical problems was first reported.
“You’ve done a great job, Yutu,” wrote one microblogger quoted by China’s Xinhua news service.
“Little bunny, we’re praying for you,” wrote another.
If some in China feel a personal connection with the rover, it’s partly because Chinese state media have attempted to humanize it. When Yutu got into trouble, Xinhua released a first-person “diary entry’ from the troubled rover.
“Although I should’ve gone to bed this morning, my masters discovered something abnormal with my mechanical control system,” Xinhua quoted Yutu as saying. “My masters are staying up all night working for a solution. I heard their eyes are looking more like my red rabbit eyes.”
Although Yutu is partly a propaganda tool, researchers within and without China see it as a serious scientific endeavor that, up until its recent troubles, they were monitoring with high expectations. The lunar rover is equipped with technology that didn’t exist in 1976, including ground-penetrating radar that scientists hoped would reveal what makes up the layers of minerals and gases 100 feet or more beneath the moon’s surface.
Some Chinese scientists are known to be interested in the moon’s deposits of helium-3, an isotope that’s been talked about as a potential source for fusion energy, despite the challenges involved with developing that form of nuclear power.
“Everyone knows fossil fuels such as gas and coal will be used up one day, but there are at least 1 million metric tons of helium-3 on the moon,” Ouyang Ziyuan, a senior adviser to China’s lunar program, told Xinhua.
Images delivered by Yutu have enthralled space enthusiasts, but it might take some time to see whether the rover, after just a few weeks on the moon, was able to transmit data of long-term scientific value.
“The photography is excellent. These are our first views from the lunar surface in more than a generation,” said Morris Jones, an Australian space analyst and writer. “The other data is fairly solid science, but it will take more time to analyze the data.”
Johnson-Freese said China’s robotic lunar program was a “great symbolic exercise in ‘techno-nationalism,’ demonstrating power through technology, and gaining national prestige through technology.” But she added that China has made extra efforts to ensure that Yutu’s science has international credibility.
Named after a character in Chinese mythology, Yutu now sits in a part of the moon known as the Bay of Rainbows. It’s an area known to be rich in titanium and other metals, and scientists had hoped that the rover would bring back soil samples that would help answer questions about the moon’s interior and volcanic history.
Yutu’s followers won’t know whether the mission can be salvaged until the rover emerges from the lunar night and gets the sunlight it needs to re-power its systems.
If Yutu doesn’t recover, however, it’s unlikely to derail China’s ambitions for the moon and beyond. China plans to put a space station into low Earth orbit by 2020, and it’s floated the prospect of putting a human back on the moon.
Johnson-Freese said China surely would learn from Yutu’s misfortunes but probably would have preferred to learn from success.
“The potential breakdown of Jade Rabbit will vividly demonstrate to China what they likely knew already, and in fact all space-faring nations know, that working in space and operating equipment in space is hard,” she said.