Chang’e-5 Orbiter Enters Sun-Earth Lagrange Point

The PolyU-developed system successfully completed the automatic sample collection and packaging on the lunar surface, and is currently on the journey back to Earth. (Credit: Hong Kong Polytechnic University)

BEIJING (CNSA PR) — The Chang’e-5 orbiter has entered a periodic orbit near the Sun-Earth L1 point, achieving the first-stage expansion mission goal and becoming my country’s first spacecraft to enter the Sun-Earth L1 periodic orbit. At present, the whole machine has stable attitude, balanced energy, and normal working conditions. It runs for about 6 months in this orbit.

The Chang’e-5 orbiter separated from the returner on December 17, 2020. After being transferred to the long-term management stage on December 21, it carried out two orbital maneuvers and two midway corrections. After 88 days of flight, it was At 13:29 on the 15th, it successfully entered the periodic orbit near the sun-earth L1 point and carried out follow-up missions.

The full name of “solar-earth L1 point” is “solar-earth Lagrangian L1 point”, which is located between the line of the sun and the earth, about 1.5 million kilometers away from the earth. At the “sun-earth L1 point”, the relative position of the object relative to the sun and the earth remains basically unchanged. 

There are periodic orbits and quasi-periodic orbits near the Lagrangian point. In theory, spacecraft can move along these orbits and observe the sun or the sun-facing surface of the earth without interruption.