By Ishita Moghe, January 5 2020—
China’s Chang’e-5 spacecraft is bringing lunar samples to Earth for the first time in forty-four years. The last spacecraft to collect lunar soil and rock samples was the (then) Soviet Union’s Luna 24 in 1976. Chang’e-5 lifted off on a Long March 5 rocket on Nov. 23. This mission included significant firsts both for China and the world. As the Chinese National Space Administration’s (CNSA) most ambitious space mission yet, Chang’e-5 puts the country on the map in terms of space exploration, as they were notably able to pull off the first autonomous rendez-vous in lunar orbit.
Chang’e-5 successfully landed in the Oceanus Procellarum (Ocean of Storms), a region known to contain volcanic material, on Dec. 1. The CNSA released close-up footage taken by the lander while coasting above the lunar surface searching for a place to land and while descending to the surface.
Chang’e-5’s mission is to return around 4.5 pounds of lunar material to Earth to advance our understanding of lunar geomorphology. After landing, Chang’e-5 used its 2-meter long core drill to retrieve a vertical soil sample that includes surface and subsoil samples. It also scooped surface samples and took photos while parked on the moon. A spectacular panoramic shot was released giving a detailed view of the landing site and the surrounding region of mountains and craters, showing us a different view of the moon than previous Apollo mission images. The lander deployed the Chinese flag, making China only the second country to have a flag on the moon after the USA.
The specific landing site was a volcanic mound called Mons Rümker. It was chosen as it contains ‘younger’ rocks — while the Apollo samples were more than 3 billion years old, the Chang’e-5 samples are expected to be less than 2 billion years old. Additionally, the landing region contains unexpected amounts of specific elements such as potassium, phosphorous, and radioactive elements thorium and uranium. These new samples will help scientists better understand the moon’s history and perhaps shed insight into long-standing questions about lunar timescales and geologic activity.
After about a day, the lander had collected enough sample material and ascended to lunar orbit. It completed the first ever autonomous rendez-vous in lunar orbit to dock with its return vehicle. A space rendez-vous involves two spacecrafts approaching each other very closely while in orbit. This maneuver requires extreme precision to align orbital velocities and position vectors such as angle, speed, and spin in three-dimensional space. Chang’e-5 was the first spacecraft to autonomously rendez-vous and dock with a spacecraft already waiting in lunar orbit, with no human input. After successfully docking, the lunar soil samples were transferred to the return vehicle, and it began its journey back to Earth. The spacecraft is expected to return in mid-December, bringing with it the first lunar samples to arrive on Earth since 1976.