Chang'e–4 probe enters elliptical lunar orbit for moon-landing
By Shan Xin
People's Daily app


At 8:55 am (Beijing Time) on Sunday morning, China’s lunar probe Chang’e-4 has successfully changed orbit in preparation for the first-ever soft landing on the moon’s far side. Once again, China is on the threshold of a historic first in its fast-paced exploration of Earth’s moon.

The probe injected maneuver parameters at 4:55 am and its engine successfully ignited four hours later, which allows the probe to get into an elliptical lunar orbit with the perilune at about 15 km and the apolune at about 100 km at 8:55 am, said CNSA.

Since the Chang'e-4 entered the lunar orbit on Dec. 12, the ground control center in Beijing has trimmed the probe's orbit twice, as well as made four tests on the communication link between the probe and the relay satellite Queqiao, or Magpie Bridge, which is operating in the halo orbit around the second Lagrangian (L2) point of the earth-moon system.

The space engineers also checked the imaging instruments and ranging detectors on the probe to prepare for the landing.

The control center will choose a proper time to land the probe on the far side of the moon, according to CNSA. 

Having sent three previous missions moonward since 2007, including one that hosted the nation’s first-ever robotic lander and rover, China’s latest lunar foray began in the early hours of Dec. 8, 2018, when a Long March-3B carrier rocket launched from the Xichang Satellite Launch Center in Southwest China’s Sichuan Province, carrying the Chang’e-4 spacecraft. Consisting of a lander and a rover, Chang’e-4 targets the moon’s far side, the lunar hemisphere that is always facing away from Earth. No spacecraft has ever achieved a soft landing there before, although in 1962 NASA crashed its Ranger 4 probe into the far side surface.