Leonard David's INSIDE OUTER SPACE

China’s next Moon exploration phase: Sample return from the Moon.
Credit: CCTV/Screengrab/Inside Outer Space

China is poised to reactivate this year Moon sample return via the country’s Chang’e-5 lunar mission. That prospective outing get’s the go-ahead depending on an upcoming return-to-flight of a Long March-5 carrier rocket this July.

Long March-5 booster’s first liftoff occurred in early November 2016. Mishap on launcher’s second flight in July 2017. A return-to-flight Long March-5 mission is slated for this July.
Credit: CASC

If that third flight is successful, the fourth Long March-5 carrier rocket will be tasked to send the Chang’e-5 lunar probe to the Moon to bring lunar samples back to Earth at the end of 2019.

Soviet Union’s last Moon sample mission, Luna 24 sits on the edge of a 60 meter diameter crater. Photo taken by NASA’s Lunar Reconnaissance Orbiter Camera, or LROC.
Credit: NASA/GSFC/Arizona State University

Given victory, it would be the first lunar-sample-return mission in over four decades after the former Soviet Union’s Luna 24 project in 1976. That mission collected and returned to Earth 170 grams of Moon material.

Complex mission

Chang’e-5 is a multifaceted mission, divided into 15 sub-systems, including structure, thermal control, antenna, sample collecting and sealing and propulsion. It is composed of an orbiter, a returner, a lander and an ascender.

According to Peng Jing, deputy chief designer of the probe from the China Academy of Space Technology, Chang’e-5 will first enter an Earth-Moon transfer orbit. It will then slow near the Moon, entering lunar orbit, followed by descent of a lander, touching down at a pre-selected area for ground research work, including collecting lunar samples.

Sealed container

After completing its work on the Moon, the Chang’e-5 mission’s ascender will rise from the lunar surface for rendezvous and docking with the orbiter flying around the Moon. Then the returner — carrying the lunar collectibles — will fly back to Earth via transfer orbit, reenter the atmosphere and land at the Siziwang Banner (County) of Inner Mongolia Autonomous Region, Peng said in a recent China Central Television (CCTV) interview.

The lunar samples rocketed back to Earth by the Chang’e-5 probe will be sealed in a container and sent to labs for further analysis and research, Peng added.

Ground facility

Meanwhile, China has designed and completed fabrication of a ground facility to handle and study returning Moon specimens.

In a paper prepared for the 50^th annual gathering of scientists at the Lunar and Planetary Science Conference (LPSC) to be held mid-March, a Chinese research team is slated to detail a lunar sample facility.

A key task, they note, is to collect lunar soil and rock samples and to seal them in good condition for scientific research here on Earth. The design of an advanced ground facility has been done, they add, geared to open sealed samples and transfer those treasured specimens in a way that they are free of contamination.

Map of Rümker region, target of Chang’E-5 sample return mission. Credit: Y. Qian, et al.

Credit: New China/Screengrab

Grasp and drill

China’s Chang’e-5 sample return mission plans to return over four pounds (2 kilograms) of lunar samples from the Moon’s Rümker region, explains Yuqi Qian of the School of Earth Sciences at the China University of Geosciences in Wuhan. Touchdown of the craft is within a zone of roughly 370 miles x 78 miles (600 kilometers × 125 kilometers).

The Rümker region is located in northern Oceanus Procellarum of the Moon and is the most distinctive geological feature in the area. The region is characterized by prolonged lunar volcanism. “In order to pick a science-rich site, many studies have been conducted and the Rümker region was selected and characterized for its geomorphology and geology,” Yugi and colleagues note in their LPSC abstract.

Apollo 15 image captures landing locale of China’s Chang’e-5 Moon lander – the Mons Rümker region in the northern part of Oceanus Procellarum.
Credit: NASA

There are two ways Chang’e-5 will acquire samples:  grasp from the surface and drill into the surface to 6.5 feet (2 meters) depth. A ground drilling simulation using lunar regolith simulants has already been carried out using a system that resembles the equipment onboard the Chang’e-5 spacecraft.

Lunar research station

In another LPSC presentation, Lin Xu, General Office of the Lunar and Deep Space Exploration is on tap to detail China’s Moon plans. On the basis of the current lunar exploration, Chinese scientists and technical experts have proposed a tentative plan by several missions to preliminarily build a lunar research station at the Moon’s South Pole by implementing three to four missions before 2035.

The first mission will carry out comprehensive exploration in the South Pole of the Moon, including the topography, elemental composition and volatile contents of the Moon. Water ice in the permanently shadowed areas is one target of the investigation, Lin and colleagues are to explain.

After that, a sampling return mission will collect samples from the South Pole of the Moon and return them to the Earth. In addition to the scientific exploration of the Moon, the utilization of lunar resources is to be considered. In later missions, lunar platforms will be used to make astronomical or Earth observations and to consider the utilization of lunar resources, the Chinese lunar researchers note in their LPSC abstract.