China delivers sampling probe to the moon – Astronautics now

The shadow of one of Chang’e 5’s landing legs can be seen in this image of the spaceship after it touched the moon on Tuesday. Credit: CNSA

A Chinese spacecraft successfully touched the moon on Tuesday, starting with what the engineers described as the mission’s biggest challenge to drill, shovel and seal the rocks to return to orbit at the end of the week and return to Earth in mid-December.

The Chang’e 5 landing unit is in the Moon Oceanus Procellarum, or Ocean of Storms region, in the northern hemisphere near the Moon, east of a volcanic plateau called Mons Rümker.

The landing took place at 10:11 a.m. (EST 1511) on Tuesday, according to the China National Space Administration. The space agency reported that the lander had touched the moon at 43.1 and 51.8 degrees west longitude.

The robot sample return mission launched from China’s Wenchang spaceport on November 23 aboard a heavy-duty Long March 5 missile and then arrived in orbit around the moon on Saturday.

The Chang’e 5 mission landing craft detached from its runway and return leg on Sunday to begin a series of descent maneuvers.

According to the CNSA, the last descent of the Chang’e 5 began at 9:57 a.m. (1457 GMT) EST at a speed of 9.87 mph (1.7 km) per second with the braking of a 1,700-pound throttle engine, ending in a short hover of around 300. feet or 100 meters above the lunar surface for on-board sensors to find a smooth landing location.

After reaching the surface, the spacecraft deployed solar panels and a communications antenna to begin its two missions on the moon, the CNSA said.

Tuesday’s landing signaled that frenetic activity would begin on the surface of the Moon. The Chang’e 5 lander is expected to begin digging in the lunar crust within a few hours of arriving at the Moon, first collecting rocks with a drill and then a spoon on a robotic arm to return to Earth.

If successful, Chang’e 5 will be the first mission to bring the rocks back from the Moon since the 1976 Luna 24 missions in the Soviet Union.

The Chang’e 5 was designed to extract up to 4.4 pounds or 2 kilograms of material from a depth of up to 2 meters below the lunar surface.

If all goes according to plan, the Chang’e 5 take-off vehicle will take off on Thursday to climb back into orbit around the Moon and use the landing platform as a take-off station. The ascending vehicle is expected to meet on the orbit around the moon on Saturday and dock with the mission’s return module, then transfer the lunar samples to the orbit. The returning ship will begin maneuvers to set off for Earth in mid-December for a high-speed re-entry and landing in China’s Inner Mongolia region.

The successful landing on Tuesday was the third time China had slipped onto a spacecraft on the moon, following the 2013 Chang’e 3 mission and the 2019 Chang’e 4. The Chang’e 4 became the first spacecraft to make a soft landing on the other side of the moon, a feat made possible by the placement of a purpose-built Chinese data satellite in deep space.

Chang’e 3 and Chang’e 4 carried rovers to serve as mobile scouts to explore the lunar landscape. Chang’e’s 5 missions have no mobile rover on the surface of the Moon.

Clive Neal, a lunar researcher at the University of Notre Dame, said he had demonstrated with previous Chinese missions that he could land on the moon.

“But then they have to collect the sample,” Neal said in an interview shortly after the start of Chang’e 5. “The interesting thing is that they set off from the Moon, get into the Moon’s orbit, and then meet the Earth’s returning vehicle, which brings this pattern back to Earth safely and uncompromisingly. When the Soviets last did this in 1976, it was aimed directly at Earth. They set off from the moon and came straight back to Earth. This has an extra step that needs to go well for the sample to really get back.

“But given the ability they did for the first time, like landing on the far shore and wandering around, I hope things will be successful and I hope they succeed,” Neal said in a Spaceflight Now interview.

“We have never completed a full sampling and sealing process,” Peng Jing, chief designer of the Chang’e 5 Mission of the Chinese Space Academy, said in an interview broadcast on China’s state-owned CCTV television channel. “This part of the work depends mainly on several complex structures, including the drill robot robotic arms, which are used to explore rock and regolit on the surface of the moon, and in fact a high-vacuum sealing device designed to ensure that the sample remains intact. “

Scientists want to make sure lunar samples are sealed to return to Earth to avoid contamination.

Another challenge will be the launch of Chang’e 5 from the surface of the Moon, the first take-off from the Moon since the 1970s. The ascending module must start on an exact orbit to meet the return module on the orbit around the Moon, and the ground troops only knew the exact direction of the landing on the surface of the Moon after reaching the ground.

“We need to accurately predict the location and speed of the two spacecraft holding in,” Peng told CCTV. “Because the probes don’t match the size – our ascent weighs just about 300 to 400 kilograms (660 to 880 pounds) while docking, while the (circulating) weighs almost 2,000 kilograms (4,400 pounds). Any mistake can hit smaller spaceships, making it much more difficult to dock work than before.

After transferring the samples to the Earth’s returning spacecraft, Chang’e sends out 5 fire engines to break out of the Moon’s orbit and head home.

The returning carrier returns to the atmosphere at about 25,000 km / h, or 40,000 kilometers / hour, significantly faster than returning from a low Earth orbit. The capsule lands around Dec. 15 in the Inner Mongolia region of China, where troops extract lunar samples and deliver the material to a lab for analysis.

Nine missions brought the lunar samples back to Earth, including NASA’s six Apollo missions with astronauts and three Luna robots launched by the Soviet Union. NASA’s Apollo missions brought 842 pounds (382 kilograms) of rock back from the moon.

There is evidence that the rocks in Chang’e’s 5 landing zone are much younger than the rocks returned by Apollo astronauts. These specimens are about 3.5 billion years old, created during the period of active volcanism in the first billion years of the Moon’s existence.

The lava plains east of Mons Rümker appear to be less affected by the effects of the asteroid, suggesting that the rocks there may be less than 2 billion years old. But models of the moon’s evolution suggest that by then its internal heating should have been reduced, making volcanoes extinct, Neal said.

“It will be exciting to see the return of these patterns and their actual composition,” Neal said.

“We haven’t been sending a sample of the Moon for 44 years, since Luna 24, a long time ago,” James Head, a planetary scientist at Brown University, said in an interview broadcast on the Chinese CGTN television network. “The best way to get to know the Moon is to send back samples. This is true for all planetary bodies because in the lab we can perform analyzes that are much better than what we know remotely or in situ. “

“Chinese scientists have said that samples of different ages are needed to form a complete picture of the Moon,” Peng said. “Analysis suggests that samples collected from the northwestern region of Oceanus Procellarum are relatively young. If we combine these patterns with the previous ones, we will better understand the formation and evolution of the Moon. “

Email to author.

Follow Stephen Clark on Twitter: @ StephenClark1.