Chinese space engineers designed multiple launch windows for the Chang'e-6 mission, which will greatly secure the success rate and reliability of the upcoming launch mission.
The Chang'e-6 lunar probe is scheduled to be launched at an appropriate time in the beginning of May, according to the China National Space Administration (CNSA).
The combination of the Chang'e-6 lunar probe and the Long March-5 Y8 carrier rocket was transferred vertically on Saturday to the launch area at the Wenchang Spacecraft Launch Site in south China's Hainan Province, the CNSA said.
Experts said that due to the constant changes in the relative position of the Earth and the Moon, if the launch cannot be carried out within the launch window, the entire mission will be affected. In order to ensure that Chang'e-6 has the best entry into orbit, the rocket team used "narrow window multi-orbit" launch technology.
“The signature feature of the Chang'e-6 mission is that it has extra high requirements for the launch window, mainly due to the lunar orbit. In order to achieve an optimal energy, it has a high requirement for the launch time of the rocket and the time of delivery to the Lunar Transfer Orbit (LTO), so the launch window is relatively narrow. We have carried out some verifications for the ‘narrow window and multi-orbit’ technology,” said Zhu Hai Yang, a staff member with the China Academy of Launch Vehicle Technology.
For this launch, researchers designed 10 lunar orbits for the rocket, which greatly secured the launch success rate and reliability. At the same time, the Chang'e-6 probe needs to enter the LTO with a perigee of 200 kilometers and an apogee of 410,000 kilometers, and the requirement for orbit entry accuracy is also extremely high.
"As for the rocket, we mainly need to send it to the LTO transfer point. In terms of process coordination before launching at the launch site, coordination and drills were also carried out around the narrow window multi-orbit technology. With higher accuracy in orbit insertion, less propellant will be consumed by Chang'e-6 for its attitude adjustment, including orientation, orbit elevation, and orbit change," Zhu said.
Researchers design multiple launch windows for China's Chang'e-6 mission
