Workers prepare for the launch of the Long March-5 rocket, which will carry the Chang’e-5 lunar mission, at the Wenchang Space Launch Center in southern China’s Hainan province on Nov. 23, 2020. (Tingshu Wang/Reuters) China is preparing to send an unmanned spacecraft to a previously unexplored part of the moon on Tuesday in a bid to bring back material that could help scientists better understand the satellite’s origins. Only the United States and the Soviet Union have successfully brought lunar material back to Earth. Chang’e-5 is scheduled to launch from the Wenchang Space Launch Center in Hainan province between 4 a.m. and 5 a.m. local time Tuesday. The mission is named for the Chinese goddess of the moon. The Long March-5 launch rocket carrying the Chang’e-5’s four modules — the lander, the ascent vehicle, the service capsule and the return capsule — began its fueling process on Monday, Chinese state media reported. The lander is scheduled to touch down in an area called Oceanus Procellarum and stay on the moon for only as long as one lunar day — the equivalent of around two weeks on Earth. Once there, it will attempt to dig about seven feet into the ground, then transfer the collected material to the ascender. According to NASA , the ascender will then dock on the service capsule, at which point the samples will be transferred to the return capsule. That capsule will then return to Earth, where it is expected to land in Inner Mongolia early next month. The mission’s goal is to collect about 4.5 pounds of material for research. Jack Singal, an associate professor of physics at the University of Richmond, said that — if successful — the mission will allow scientists to directly date the rocks and volcanic activity from the collection site. By then calibrating the age to crater density, he said, it could set the stage to “give us a better handle on dating rocks on the rest of the surface of the moon and other rocky bodies,” including Mercury and Mars. The mission, Singal said, is “an appropriate-scale mission for an emerging space power.” The endeavor is the latest in China’s ambitious plans to expand its research in space, a rivalrous aspect of the U.S-China relationship. In July, China launched its Tianwen-1 mission, marking the country’s first attempt to land a rover on Mars. NASA launched its Mars mission, called Perseverance, the next week. The United Arab Emirates also launched an orbiter to Mars that month. In January 2019, China became the first country to successfully land a spacecraft on the far side of the moon. On that mission, called Chang’e 4, the craft landed in the Von Kármán crater, located in the South Pole-Aitken basin. The Chinese National Space Administration said the landing “marked a new chapter in the human race’s lunar and space exploration.” NASA Administrator Jim Bridenstine calling that landing “a first for humanity and an impressive accomplishment.” China has dramatically accelerated its space missions in recent years, after first launching an astronaut into space in 2003, decades after American astronauts’ 1969 moon landing. China’s latest mission was originally scheduled for 2017, but it was delayed after a Long March 5 launch failure. The most important news stories of the day, curated by Post editors and delivered every morning.