摘要
Until 2019,astronauts and robotic spacecraft had only landed on the near side on the Moon—the side permanently facing the Earth.On 3 January 2019,China’s Chang’e-4 became the first space mission to touch down on the Moon’s far side(Fig.1),most of which is not visible from Earth[1].‘‘Chang’e-4 is quite a remarkable accomplishment,”said planetary geoscientist James Head of Brown University in Rhode Island,USA.It is the latest success for the ambitious Chinese space program,which later in 2019 will launch a spacecraft to retrieve samples from the lunar surface and in 2020 plans to send a probe to Mars.