Shenzhou-11 docks with Tiangong-2 in latest Chinese space station mission
The Chinese spacecraft Shenzhou-11 – and its crew of two taikonauts – has successfully docked with the Tiangong-2 space module at 19:24 UTC. The docking begins a month long mission in which the crew will conduct a series of experiments aimed at progressing China’s ambitions in space.
The launch was followed around the world and gained huge domestic interest.
A massive – and somewhat choreographed – crowd chanted in support of the taikonauts as they departed for the launch site under a police escort.
The launch countdown proceeded without issue as the Long March carrier rocket propelled the crew into orbit.
Following Sunday’s successful launch, Shenzhou-11 – and its two taikonauts – were inserted into a parking orbit.
The Chinese manned spacecraft was detected on a 334 x 336 km x 42.8 deg orbit. With the spacecraft using its own propulsion system, its orbital parameters were raised to a near circular orbit with an altitude of 393 km.
The spacecraft took two days to transition into rendezvous operations with Tiangong-2.
During Shenzhou-8 and Shenzhou-9 missions to Tiangong-1, the rendezvous was conducted via the V-bar approach. During Shenzhou-10, the three member crew also practiced the approach to the old station using the R-bar approach and then maneuvering to the docking port.
Back then, Chinese specialists said that the test made with SZ-10 was a key docking objective ahead of the construction of the future Tiangong modular space station that China will launch during campaigns in 2018.
China also has Lunar and Mars ambitions that they will build from the experiences of the Tiangong missions.
For Shenzhou-11, the approach used the V-bar approach to dock with Tiangong-2.
For rendezvous and docking, operations began at a distance of 52 km from the space module with the monitoring center system analyzing the parameters of Shenzhou-11. At this distance both spacecraft will have been able to read the relative position and velocity of each other.
The next phase of the automatic approach and docking operations began when the two vehicles were 20 km apart, as Shenzhou-11 moved towards the three Go/No Go points – at 5 km, 400m, 140m and 30m.
During these “parking points”, the relative position of the spacecraft were assessed by ground controllers before a go to proceed was given.
At 120 meters the taikonauts had the option to take manual control of Shenzhou-11 if this proves necessary. This process is common for docking vehicles of all nationalities.
During these rendezvous operations, Shenzhou-11 provided the role of the “active vehicle”, while the Tiangong-2 acted as the “passive vehicle”. At a distance of 30 meters, the docking mechanism was extended to achieve the soft docking with the orbital module.
As the distance between the two vehicles continued to close, the ground control data continued to increase in accuracy, allowing for the final approach and soft dock. This was marked at 19:24 UTC.
It took 15 minutes to provide a hard dock/seal between the two vehicles, which allowed the control center to adjust the cabin environment.
Once the leak checks were completed, the crew enter the module and began taking measurements into cabin pressure, oxygen capacity, air temperature and humidity, along with checks into potentially harmful gasses.
Living in orbit:
As previously announced by the Chinese authorities, docked operations with Tiangong-2 will last 30 days. It is expected that the two taikonauts will sleep in the new station where there are two dedicated sleeping areas that are each equipped with two-way video communications equipment.
Tiangong-2 is equipped with everything a taikonaut needs, including exercise equipment, medical laboratory equipment, waste recycling equipment, medical health monitoring equipment, among other essentials.
Also on board are various clothing packages, including thermal underwear, warm pants, sports shoes, sportswear and shorts.
At launch, Shenzhou-11 itself carried more than 300 kg of cargo, including water, food rations and experiments with it to the module.
While in orbit, medical examinations will be conducted, including on-orbit examinations of the crew’s hearts, lungs and biochemistry conditions, as well as providing effective prevention against space motion sickness.
For this, equipment ranging from a bicycle ergometer to a chest developer and neuromuscular electrical stimulation have been prepared on board Tiangong-2 to protect the taikonauts against weightlessness and maintain their cardiac and muscular functions.
The two man will also wear the so called ‘penguin suit’ that will help them to countermeasure the effects of the weightless environment.