Chinese spacecraft reenters atmosphere ahead of new space station missions

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HELSINKI — China deorbited the Tianzhou-2 cargo spacecraft Thursday after testing on-orbit docking, refueling and module transposition for the Chinese space station.

Tianzhou-2 reentered the atmosphere over the South Pacific at 6:40 a.m. Eastern March 31, China’s human spaceflight agency, CMSA, announced minutes after the event. The area of the ocean is frequently used as a “spacecraft cemetery.”

The spacecraft separated from the forward docking port of Tianhe, the core module of China’s space station, at 3:59 a.m. Eastern March 27.

Tianzhou-2 makes way for the arrival of the Tianzhou-4 cargo spacecraft which will provide fresh supplies and fuel ahead of the arrival of the Shenzhou-14 crew, with the latter expected to launch around mid-to-late May. 

The 10-month-long mission verified a number of technologies and procedures needed to proceed with future construction of the Chinese space station.

 Tianzhou-2 launched May 29, 2021, on a Long March 7 rocket from Wenchang. It completed automated rendezvous and docking maneuvers with Tianhe just over eight hours later. 

The 13.5-ton spacecraft was the first to join the Tianhe module in orbit, verifying on-orbit docking and refueling required for further missions to begin. It delivered 4.69 tons of cargo in a pressurized segment, including three months’ worth of food for three Shenzhou-12 crew members and two EVA suits. 

It also carried 1.95 tons of propellant to the 22.5-ton Tianhe module, which had launched in late April.

The spacecraft performed four rendezvous and docking maneuvers, including a manual remote operation rendezvous and docking, to test out procedures.

Tianzhou-2 was also involved in a transposition test ahead of the arrival of two future modules, Wentian and Mengtian, due to launch later in the year. 

On Jan. 5 Tianhe’s 10-meter-long robotic arm grasped Tianzhou-2, moving it roughly 20 degrees before returning it to the forward port on the Tianhe docking hub. 

Both new modules will dock with the forward port before being transposed to respective lateral docking ports, creating the finished “T-shaped” orbital outpost.

China plans six missions in 2022 to complete its space station, including two cargo and two crewed missions along with the two module launches. 

The China Academy of Launch Vehicle Technology (CALT) held a ceremony March 29 for launch teams that will be involved in the required Long March 2F, Long March 5B and Long March 7 rocket launches.

The spacecraft for the ongoing Shenzhou-13 crewed mission is currently docked at the nadir port at Tianhe and is expected to depart in mid-April. Tianzhou-4 will launch for Tianhe following this, ahead of a new crew aboard Shenzhou-14.

The 20-ton-plus Wentian and Mengtian modules will launch during the six-month-long Shenzhou-14 mission. Tianzhou-5 will launch ahead of Shenzhou-15, both scheduled for late in the year, with the latter expected to see the first Chinese crew handover aboard the completed space station.

Tianzhou-5 will also carry five small satellite payloads among a range of experiments,  CMSA announced March 30.

The module launches will be followed closely, partly due to the significance of the missions, but also because of the use of the Long March 5B, the two previous launches of which saw the large first stages make high-profile uncontrolled reentries.

The Tiangong space station is planned to operate in orbit for at least 10 years. It will host a range of international experiments through collaboration with the United Nations Office of Outer Space Affairs, and potentially foreign astronauts and further modules in the coming years.