Shenzhou-14 crew to start new era of China’s space station program – SpacePolicyOnline.com
China will launch a new crew of three to the core module of its Tianhe space station tonight. The mission marks a new era in China’s space station program as the crew oversees the addition of Tiangong-3’s two remaining modules 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 common for more than 20 years, but this is a major step in their human spaceflight aspirations. The launch is scheduled for 10:44 p.m. EDT (June 5, 10:44 a.m. Beijing time).
China officially announced the launch date and time and the crew members less than 24 hours in advance. Like Shenzhou-13, the crew consists of two men – a veteran taikonaut and a rookie – and a woman, also a veteran of a previous flight.
In fact, this is the second spaceflight of 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 for her first flight.
A lot has changed since Liu and Chen were in space before. Tiangong-1 and Tiangong-2 were tiny compared to what their new home in space will be when they return to Earth in December.
These first two Chinese space stations weighed only 8.5 metric tons (MT) each. The main module of Tianhe is 22.5 MT alone. The Wentian and Mengtian lab modules about to be added are the same size. China announced earlier this year that Wentian would launch in July and Mengtian in October.
Altogether, the three modules will form a 67 MT space station with one or two Shenzhou crewed spacecraft and one or two Tianzhou cargo ships docked at all times. By comparison, the ISS is about 420 MT plus up to eight visitor vehicles at a time: Soyuz (Russia) and Crew Dragon (US), and Progress (Russia), Cargo Dragon (US), Cygnus (United States) and Cargos HTV (Japan). NASA hopes Boeing’s Starliner crew spacecraft will begin operational flights next year.
Still, a 67 MT space station is not to be overlooked. Its size is almost comparable to that of the first American space station, Skylab, which accommodated three crews in 1973-1974, but was not intended to be permanently occupied. Tiangong-3 is and this era will begin when the Shenzhou-15 crew launches in December with a transfer of operations between the two crews.
The 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 unrolled on the launch pad last Sunday.
Chinese state news agency Xinhua said June 4 that the crew will perform two or three spacewalks during their expedition, using the airlock of the Wentian module for the first time. The first two crews to visit Tianhe, Shenzhou-12 and Shenzhou-13, conducted two spacewalks each. Wang Yaping became the first Chinese woman to perform a spacewalk last year during the Shenzhou-13 mission.
Wentian has 25 experimental cabinets to support studies of life and ecology, biotechnology, and variable-gravity research According to Lin Xiqiangdeputy director of the China Manned Space Agency.
Wentian has a small robotic arm it’s about half the weight and length of Tianhe’s with one-eighth the load capacity, but with five times the positioning accuracy and twice the attitude accuracy. It can be attached to the Tianhe arm and can crawl along the outside of the modules. Gao Sheng with the Chinese Academy of Space Technology said the 10-meter Tianhe arm and the 5-meter Wentian arm “will see the operating range expand to 14.5 meters when they form a combined operational arm” that can inspect all three modules.
17 meters from Canada Canadarm2 on the ISS crawls along the exterior and can travel the full length of the ISS according to a Canadian Space Agency fact sheet, although this is likely a reference to the segment of American operating only, not to the Russian segment.
Mengtian has a cargo airlock and a “deployed extravehicular platform” that resembles the Japanese Kibo module facilities on the ISS. Lin said planned experiments on Mengtian include studies in fluid physics, materials science, combustion science, basic physics and space technology. He added that a cold atomic clock will be installed in Mengtian. “Composed of a hydrogen clock, a rubidium clock and an optical clock, the cold atomic clock will form the most accurate time and frequency system in space” and “serve research on the gravitational redshift, measurement of fine structure constants and other applications”.
Like Tianhe, Wentian and Mengtian need the Long March 5B booster to get into orbit. It is launched from the new Wenchang Satellite Launch Center on Hainan Island.
The launch of the Tianhe module has drawn international criticism because the rocket does not perform a controlled reentry after separating from its payload. Fortunately, the body of the Long March 5B rocket 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 return safely. He told the Senate Commerce-Justice-Science Appropriations Subcommittee no later than May 3 that “it could have fallen in Europe. He could have fallen in Saudi Arabia. And they were secret about the coordinates of where he was going to fall. He said he discussed it with the Chinese ambassador. It will be interesting to see if China makes any changes for these next two mod launches.
In addition to the arrival of Wentian and Mengtian, the crew of Shenzhou-14 will be visited by the cargo ship Tianzhou-5 (Tianzhou-4 is there now).
This pace of China’s manned spaceflight program contrasts with the first two decades. China’s first astronaut, Yang Liwei, launched on Shenzhou-5 in 2003 after four uncrewed test flights between 1999 and 2002. That was two years before the next crewed mission and three years after for the third. Between 2003 and 2021, only six crews have been launched.
That started to change last year with the launch of the Tianhe module and Shenzhou-12, a three-man crew that set a new space duration record for China by three months from June to September. Then Shenzhou-13 with two men and a woman for six months (October 2021-April 2022).
Now, six-month missions with rotating crews are to be the norm, just like the ISS, although the ISS has a standard crew of seven instead of three and ISS crews are international. At the moment there are three Russians, three Americans and an Italian on board (five men, two women).
China has already invited the international scientific community to propose experiments and plans international crew members in the future.