Chinese space scientists have announced new discoveries made by Yutu-2, the first robot rover ever to explore the far side of the Moon, which permanently faces away from the Earth.
Commanding a rover on the Moon's far side presents big challenges: the Earth is always out of sight, so radio commands and data have to be bounced back and forth using a special relay satellite orbiting in space beyond the Moon. The rover relies on solar power, so it has to shut down most of its operations for two weeks of every month during a long period of lunar night. Since rolling onto the Moon from its Chang'e-4 lander in January 2019, Yutu-2 has been operating on the Moon for more than three years, making it the longest ever mission to explore the lunar surface.
One of the rover's main findings is that the soil on the far side of the Moon is a lot stickier than on the near side -- so it's more likely to stick in Yutu-2's wheels. That's because on the far side rocks have had more continuous attacks from tiny bits of space dust that heat the rocks in the soil and make them stick together in pointed shapes.
Yutu-2's journey through the lunar landscape is very slow--so far it has covered just over 1,000 metres in three years. Along the way to either side of its path, it has spotted 88 small bowl-shaped craters( 坑). Scientists think these are secondary impact craters, formed when bits of rocks were thrown out by a much bigger impact. A far largerone,called Zhinyu, was created when a big space rock hit the Moon.
As Yutu-2 continues to explore its surroundings, researchers are excited about what else it might discover. Sara Russell from London's Natural History Museum told New Scientist magazine, "It's like this whole new world to explore. We really have a lot to find out about the far side of the Moon; it's really exciting."
