HELSINKI — A Long March 5 rocket launched China’s Chang’e-5 spacecraft Monday to kick off a 23-day mission to deliver the first lunar samples to Earth since the 1970s.

The heavy-lift Long March 5 lifted off from the Wenchang Satellite Launch Center at 3:30 p.m. Eastern. The Chang’e-5 spacecraft was announced to have successfully entered its predetermined orbit around 4:45 p.m., following deployment of solar arrays. The 8.2-ton Chang’e-5 spacecraft is to begin an estimated 112-hour journey to the moon.

The mission aims to collect the youngest samples so far obtained from the moon and later land in Siziwang Banner, Inner Mongolia, around Dec. 15-16. Samples will then be transferred to specially developed facilities for handling, analyzing and storing the lunar material. 

A successful mission would make China only the third country to deliver lunar samples to Earth, after the U.S. Apollo crewed program and Soviet robotic Luna missions of the 1960s and 1970s.

Major challenges following launch include carrying out liftoff of an ascent vehicle from atop the lander spacecraft on another planetary body, as well as a later automated lunar orbit and rendezvous around 380,000 kilometers from Earth.

Launch preparations at Wenchang have been ongoing since mid-September. The fourth and mostly recent Long March 5 mission rocket successfully launched the Tianwen-1 Mars spacecraft in July.

The Failure of the second Long March 5 launch in July 2017 meant a delay of three years for Chang’e-5, having been scheduled to launch later that year.

Mission timeline

A detailed timeline of the mission has not been released by China. The spacecraft is expected to be inserted into a roughly 200-kilometer altitude lunar orbit shortly after sunrise over the designated Mons Rümker on November 27.

The landing attempt is expected in the days following. Chinese language journals detailing the Chang’e project technology roadmap state that sampling activities will last around two Earth days. Around two kilograms of drilled and scooped samples will then be sent into lunar orbit by a roughly 500-kilogram ascent vehicle. A two-day period will conclude with rendezvous and docking between the ascent and service modules. The samples will be transferred to a reentry capsule attached the service module. 

The service will then separate from the ascent vehicle and remain in lunar orbit until an opportune window to return to Earth. The reentry vehicle will separate from the service module around 5,000 kilometers from Earth. A skip reentry, involving bouncing off the atmosphere—a maneuver tested by the Chang’e-5 T1 mission in 2014—to deal with the high-velocity return from the moon will follow. ESA tracking stations will support this critical phase as the spacecraft attempts reentry. 

Samples will then be transferred to specially constructed facilities for handling, analyzing and storing the lunar material.

Science goals

The stated landing area surrounds Mons Rümker, a volcanic peak situated in the Oceanus Procellarum region of western edge of the near side of the moon. The area may contain geological units of basaltic rock as young as around 1.21 billion years old. By comparison samples brought to Earth by Apollo astronauts are aged between 3.1 and 4.4 billion years old.

It is hoped that such geologically young samples, if returned, will allow radiometric dating of the samples to verify the age of the area. It could also then provide valuable information about the apparent late-stage volcanism needed to create the relatively new units of rock. The combination of orbital observations of cratering and accurate dating of samples would both help constrain chronologies on the moon and be applied as a reference for terrestrial bodies across the solar system.

The Chang’e-5 lander also carries a panoramic camera, lunar penetrating radar and imaging spectrometer for observation and analysis of the landing area.

Backup mission, future goals

Chang’e-6 is a sample return spacecraft engineered at the same time as Chang’e-5 to provide a backup in the event of failure. Success of Chang’e-5 would however see Chang’e-6 repurposed for a landing at the lunar south pole around 2023.

China has stated it will then proceed into an extended phase of lunar exploration involving Chang’e-7 and further lunar landing missions. The aim will be to establish an ‘international lunar research station’ in the mid-to-late 2020s as a precursor to crewed landings.

Sample return technology and experience developed through Chang’e-5 is also to be utilized for planned near Earth asteroid and Mars sample return missions later in the decade. The complexity of the Chang’e-5 mission profile is considered by observers to be related to future crewed lunar landing ambitions.

Quelle: SN

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Chinese space tracking ships complete monitoring of Chang'e-5 probe launch

Two space tracking ships from China's Yuanwang fleet completed their maritime monitoring of the Chang'e-5 probe launch in the Pacific Ocean on Tuesday morning.

Launched at 4:30 a.m. (Beijing Time), the spacecraft was sent into its present orbit by a Long March-5 Y5 rocket from the Wenchang Spacecraft Launch Site in south China's island province of Hainan.

About six minutes after liftoff, Yuanwang-6 detected and locked on to the target, and completed its monitoring. After the rocket traveled for more than 30 minutes, Yuanwang-5 continued the task.

The maritime monitoring process lasted a total of 1,100 seconds. The two ships sent accurate real-time data to spacecraft control centers in Beijing and Wenchang, laying the foundation for the Chang'e-5 mission.

Yuanwang-5 and Yuanwang-6 will now sail to their next mission areas, while Yuanwang-3 will participate in the follow-up monitoring work for the lunar probe. Enditem

Quelle: Xinhua

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China launches Chang'e-5 to collect, return moon samples

A Long March-5 rocket, carrying the Chang'e-5 spacecraft, blasts off from the Wenchang Spacecraft Launch Site on the coast of southern island province of Hainan, Nov. 24, 2020. China on Tuesday launched a spacecraft to collect and return samples from the moon, the country's first attempt to retrieve samples from an extraterrestrial body. (Xinhua/Jin Liwang)

China Tuesday launched a spacecraft to collect and return samples from the moon, the country's first attempt to retrieve samples from an extraterrestrial body.

A Long March-5 rocket, carrying the Chang'e-5 spacecraft, blasted off from the Wenchang Spacecraft Launch Site on the coast of southern island province of Hainan at 4:30 a.m. (Beijing Time).

Chang'e-5 is one of the most complicated and challenging missions in China's aerospace history, as well as the world's first moon-sample mission for more than 40 years.

The mission will help promote China's science and technology development, and lay an important foundation for China's future manned lunar landing and deep space exploration, said Pei Zhaoyu, deputy director of the Lunar Exploration and Space Program Center of the China National Space Administration.

Chang'e-5, comprising an orbiter, a lander, an ascender and a returner, with a total takeoff mass of 8.2 tonnes, is expected to accomplish unmanned rendezvous and docking in lunar orbit, an unprecedented feat.

After it enters the lunar orbit, the lander-ascender combination will separate from the orbiter-returner combination.

While the orbiter-returner orbits about 200 km above the lunar surface, the lander-ascender will touch down on the northwest region of Oceanus Procellarum, also known as the Ocean of Storms, on the near side of the moon in early December.

Within 48 hours, a robotic arm will be extended to scoop up rocks and regolith on the lunar surface, and a drill will bore into the ground. About 2 kg of samples are expected to be collected and sealed in a container in the spacecraft.

Then the ascender will take off, and dock with the orbiter-returner in orbit. After the samples are transferred to the returner, the ascender will separate from the orbiter-returner.

When the geometric relationship between Earth and the moon is suitable, the orbiter will carry the returner back to Earth. The returner will reenter the atmosphere and land at the Siziwang Banner in north China's Inner Mongolia Autonomous Region.

The whole flight will last more than 20 days.

Pei said if the Chang'e-5 mission succeeds, China's current lunar exploration project would come to a successful conclusion.

Named after Chinese legendary moon goddess Chang'e, China's current three-step lunar exploration program, which began in 2004, includes orbiting and landing on the moon, and bringing back samples.

Through the program, China has acquired the basic technologies of unmanned lunar exploration with limited investment, said Pei.

China is drawing up plans for future lunar exploration. To pave the way for manned lunar exploration and deep space exploration, the Chang'e-5 mission will use a sampling method different to those of the United States and the Soviet Union, said Pei.

The United States sent astronauts to the moon to collect samples. In the Soviet Union's unmanned lunar sampling missions, the spacecraft took off from the moon and returned to Earth directly.

But China chose a complicated technological approach including unmanned rendezvous and docking in lunar orbit, which could bring back more samples and lay a technological foundation for manned lunar missions, Pei said.

"Unmanned rendezvous and docking in lunar orbit will be a historic first. It will be very difficult," said Peng Jing, deputy chief designer of the Chang'e-5 probe from the China Academy of Space Technology under the China Aerospace Science and Technology Corporation.

"We could call it a milestone mission. Its success will help us acquire the basic capabilities for future deep space exploration such as sampling and takeoff from Mars, asteroids and other celestial bodies," Peng said.

The scientific goals of the Chang'e-5 mission include the investigation of the landing area to obtain the on-site analysis data related to the lunar samples, as well as systematic and long-term laboratory analysis of the lunar samples.

The landing site of Chang'e-5 will be to the west of that of Chang'e-3, which went to the moon in 2013.

This site is chosen because the region has a young geological age, younger than the sampling areas of the United States and the Soviet Union more than 40 years ago. This region has never been sampled. The new samples will be of great scientific value, said experts.

"Domestic and overseas scientists will all have a chance to get the lunar samples to be brought back by Chang'e-5 for research," Pei added. Enditem

A Long March-5 rocket, carrying the Chang'e-5 spacecraft, blasts off from the Wenchang Spacecraft Launch Site on the coast of southern island province of Hainan, Nov. 24, 2020. China on Tuesday launched a spacecraft to collect and return samples from the moon, the country's first attempt to retrieve samples from an extraterrestrial body. (Xinhua/Guo Cheng)

Quelle: Xinhua

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Commentary: China ready to share fruits of lunar exploration

China successfully launched its most complicated and challenging lunar mission on Tuesday, and is promising to share the moon samples expected to be returned by the spacecraft.

"Chinese scientists and those from other countries all have a chance to get the lunar samples to be brought back by Chang'e-5 for research," said Pei Zhaoyu, deputy director of the Lunar Exploration and Space Program Center of the China National Space Administration (CNSA).

Chang'e-5, the probe, is designed to land on the northwest region of Oceanus Procellarum, also known as the Ocean of Storms, on the near side of the moon in early December, and collect and return about 2 kilograms of samples.

If successful, it will be the first retrieval of lunar samples since the missions of the United States and the Soviet Union in the 1960s and 1970s.

More excitingly, its landing site, never sampled before, is geologically younger than the sampling areas of the U.S. and the Soviet missions, so the new samples will help fill in an important piece in the jigsaw puzzle of the moon's history.

Many foreign scientists and space agencies have contacted China to ask about using the samples for research, Pei said.

Lunar scientists will be eager to study the new samples because of what they might learn about the moon's evolution, said an article published by the journal Nature.

Aware of the scientific value, China has decided to share the lunar samples from the outset, as it has always viewed space exploration as a common cause of humanity and hoped to promote it through international exchanges and cooperation.

China has signed cooperation framework agreements with multiple international space agencies, including the UN Office for Outer Space Affairs, Russia's state space corporation Roscosmos and the European Space Agency.

Its open attitude toward international space cooperation has already brought benefits to its foreign partners. China's last lunar mission, Chang'e-4, which made the first-ever soft landing on the far side of the moon, carried payloads developed by the Netherlands, Germany, Sweden and Saudi Arabia.

About three months after the landing, the CNSA delivered the data collected by the neutral atom detector aboard the Chang'e-4 rover to Sweden, the data from the neutron radiation detector aboard the lander to Germany and the data from the low-frequency radio astronomical instrument aboard the relay satellite Queqiao to the Netherlands.

The data has helped deepen understanding of the lunar and space environment as well as solar activities.

Productive cooperation with multiple countries and international organizations has helped China accumulate experience for future collaboration.

It has opened its planned space station to international payloads, and offered to carry a total of 20 kg of payloads for both Chinese and foreign organizations in its future Chang'e-6 mission.

It is even considering launching an initiative to call for joint efforts to build an international lunar research station, said Pei.

The plans demonstrate China's commitment to international cooperation and shared growth. Although China is now taking the lead in lunar exploration through decades of independent innovation in space technologies, it has always been committed to sharing the achievements. Enditem

Quelle: Xinhua