By Dr Tony Phillips – Re-Blogged From Spaceweather
China is about to go where no one has gone before–the farside of the Moon. On the morning of Dec. 8th (Chinese time), a Long March 3B rocket is scheduled to blast off from the Xichang Satellite Launch Centre in Sichuan province, propelling a lander and rover toward the lunar farside. If the mission succeeds, it will catapult China into the forefront of lunar exploration with a landing that no other nation has even dared to attempt.
Above: An artist’s rendering of China’s Chang’e-4 lunar rover
From Earth, we can see only one side of the Moon. The other side, the lunar farside, is perpetually hidden from view. Apollo astronauts have flown over the farside of the Moon, and many satellites have photographed the Moon from behind–revealing it to be a rugged, heavily cratered landscape startlingly different from the side we typically see. But no one has ever landed there.
China’s Chang’e 4 mission aims to be the first. Reportedly, the lander will touch down inside a 186-kilometer-wide crater called Von Kármán. The crater is part of the South Pole–Aitken basin, the largest known impact structure in the Solar System. The Chang’e-4 rover will explore the landing site, probing it with ground-penetrating radar and measuring the mineral composition with an infrared spectrometer. If water is present, the rover might find it.
And that’s just the beginning. The lander will also conduct experiments in lunar gardening. A small climate-controlled greenhouse in the lander will test whether potato and thale-cress (Arabidopsis) seeds can sprout and photosynthesize in low gravity without the twin protections of a thick atmosphere and magnetic field.
Communicating with the farside of the moon is tricky. There’s no direct line of sight. To overcome this problem, on May 21, 2018, China launched a satellite named Queqiao (Chinese for “Magpie Bridge”) to relay signals between the lunar farside and Earth. Queqiao will be able to talk to ground stations in China, Argentina and Namibia, sending back radio signals and TV images. However, Chang’e 4 will have to perform the critical landing completely autonomously–a daring plan.
Landing is expected to occur early in the New Year. Stay tuned for updates and, meanwhile, congratulations to China for daring mighty things.