Shenzhou-14 Crew To Begin New Era of China’s Space Station Program

China launched a new three-person crew to its Tianhe space station core module this evening. The mission marks a new era in China’s space station program as the crew oversees the addition of the other two modules of Tiangong-3 and prepares for the first crew rotation in December. Tiangong-3 will be much smaller than the International Space Station where crew rotations have been routine for more than 20 years, but it is a major step in their human spaceflight aspirations. Launch took place on schedule at 10:44 pm EDT (June 5, 10:44 am Beijing Time).

China officially announced the launch date and time and crew members less than 24 hours in advance. Like Shenzhou-13, the crew is composed of two men — a veteran taikonaut and a rookie — and one woman, also a veteran of a prior flight.

In fact, this is the second spaceflight for China’s first woman in space, Liu Yang. She spent 13 days on China’s first space station, Tiangong-1, in 2012 with two male colleagues, Jing Haipeng and Liu Wang. This time she is joined by Chen Dong, who flew on Shenzhou-11 in 2016 to Tiangong-2, and Cai Xuzhe on his first flight.

A lot has changed since Liu and Chen were in space before. Tiangong-1 and Tiangong-2 were tiny in comparison to what their new home in space will be by the time they return to Earth in December.

Those first two Chinese space stations were just 8.5 Metric Tons (MT) each. The Tianhe core module is 22.5 MT by itself.  The Wentian and Mengtian lab modules about to be added are the same size. China said earlier this year Wentian will be launched in July and Mengtian in October.

All in all, the three modules will form a 67 MT space station with one or two Shenzhou crew spacecraft and one or two Tianzhou cargo ships docked at any given time. By comparison, the ISS is about 420 MT plus as many as eight visiting vehicles at a time: Soyuz (Russia) and Crew Dragon (U.S.) crew spacecraft, and Progress (Russia), Cargo Dragon (U.S.), Cygnus (U.S.) and HTV (Japan) cargo ships. NASA hopes Boeing’s Starliner crew spacecraft will begin operational flights next year.

Still, a 67 MT space station is nothing to sneeze at. It’s almost comparable in size to the first U.S. space station, Skylab, which hosted three crews in 1973-1974, but was not intended to be permanently occupied. Tiangong-3 is and that era will begin when the Shenzhou-15 crew launches in December with a handover of operations between the two crews.

Chinese crew launches take place from the Jiuquan Satellite Launch Center in the Gobi desert on Long March 2F rockets. The Shenzhou-14 rocket and spacecraft rolled out to the launch pad last Sunday.

China’s state news agency Xinhua said on June 4 that the crew will conduct two or three spacewalks during their expedition, using the airlock in the Wentian module for the first time. The first two crews to visit Tianhe, Shenzhou-12 and Shenzhou-13, did two spacewalks each. Wang Yaping became the first Chinese woman to conduct a spacewalk last year during the Shenzhou-13 mission.

Wentian has 25 experiment cabinets to support studies on life and ecology, biotechnology, and variable gravity research according to Lin Xiqiang, deputy director of the China Manned Space Agency.

Wentian has a small robotic arm that is about half the weight and length of the one on Tianhe with one-eighth the load capacity, but with five times the positioning accuracy and twice the attitude accuracy. It can be joined with the Tianhe arm and can crawl along the outside of the modules. Gao Sheng with the China Academy of Space Technology said the 10-meter Tianhe arm and the 5-meter Wentian arm “will see the operation range extend to 14.5 meters when they form a combined operational arm” that can inspect all three modules.

Canada’s 17-meter Canadarm2 on the ISS crawls along the outside and can travel the entire length of the ISS according to a Canadian Space Agency fact sheet, although that probably is a reference to the U.S. Operating Segment only, not the Russian segment.

Mengtian has a cargo airlock and a “deployed extravehicular platform” which sounds similar to facilities on Japan’s Kibo module on the ISS. Lin said experiments planned on Mengtian include studies of the physics of fluids, material science, combustion science, basic physics, and space technology. He added that a cold atomic clock will be established in Mengtian. “Consisting of a hydrogen clock, a rubidium clock and an optical clock, the cold atomic clock will form the most precise time and frequency system in space” and “serve the gravitational redshift research, measurement of fine structure constants, and other applications.”

Like Tianhe, Wentian and Mengtian require the Long March 5B booster to get to orbit. It launches from the new Wenchang Satellite Launch Center on Hainan Island.

The launch of the Tianhe module sparked international criticism because the rocket does not make a controlled reentry after separating from its payload. Fortunately the Long March 5B rocket body landed in the Indian Ocean, but NASA Administrator Bill Nelson continues to denounce China’s decision not to ensure the rocket has enough fuel to reenter safely. He told the Senate Appropriations Commerce-Justice-Science subcommittee as recently as May 3 that “it could have come down in Europe. It could have come down in Saudi Arabia. And they were secretive about the coordinates of where it was going to come down.” He said he discussed it with the Chinese ambassador. It will be interesting to see if China makes any changes for these next two module launches.

The three modules will form a T shape when construction is completed and have a habitable volume of about 100 cubic meters, compared to 388 cubic meters on the ISS not including visiting vehicles.

In addition to the arrival of Wentian and Mengtian, the Shenzhou-14 crew will be visited by the Tianzhou-5 cargo ship (Tianzhou-4 is there now).

This pace for the Chinese human spaceflight program stands in contrast to the first two decades. China’s first taikonaut, Yang Liwei, launched on Shenzhou-5 in 2003 after four uncrewed test flights between 1999 and 2002. It was two years before the next crewed mission and three years after that for the third. Between 2003 and 2021, only six crews were launched.

That began changing last year with the launch of the Tianhe module and Shenzhou-12, a three-man crew who set a new space duration record for China of three months from June-September. Then Shenzhou-13 with two men and one woman for six months (October 2021-April 2022).

Now six-month missions with rotating crews are to be the norm, just like ISS although ISS has a standard crew complement of seven rather than three and the ISS crews are international. Right now there are three Russians, three Americans and an Italian aboard (five men, two women).

China has already invited the international science community to propose experiments and plans international crewmembers in the future.

 

Note: this article was updated after the successful launch at 10:44 pm EDT June 4.