China's Space Station: Tianhe-1 module to be followed by Tianzhou-2, Shenzhou-12
The core module of the Chinese Space Station, Tianhe-1, will be launched in 2018, says Zhang Bainan, chief designer of crewed spacecraft at the China Aerospace Science and Technology Cooperation (CASC).
This will be followed by Tianzhou-2, a cargo and refuelling spacecraft, which will dock with and supply Tianhe-1 in low Earth orbit.
After this the Shenzhou-12 crewed spacecraft will visit Tianhe-1, which is the first of three large modules that will make up the completed Chinese Space Station (CSS).
The launch order was revealed to press in Beijing at the country's ongoing annual parliamentary sessions by Mr. Zhang, whose given name is also pronounced 'Bonan', though no dates were offered.
Construction of the 20 metric tonne Tianhe-1 core module was completed in late 2016 and has entered a testing phase.
Above: Rendering of the Tianhe-1 Chinese Space Station core module (CMSA).
Tianhe-1 will be launched from Wenchang by a Long March 5B rocket, a low Earth orbit variant of a new generation heavy-lift launch vehicle that debuted last year and will in November launch a lunar sample return mission, Chang'e-5.
The Tianzhou cargo spacecraft will next month have its first flight via a Long March 7 rocket to test liquid propellant refuelling in microgravity, once it docks with the orbiting Tiangong-2 space lab, a small 8-tonne testbed for CSS modules.
The mission will test and verify the crucial refuelling technologies and processes needed to maintain the future Mir-class CSS.
Shenzhou-12 will be China's seventh crewed spaceflight mission, following Shenzhou-11 last October which doubled the country's record for human spaceflight duration.
Above: Jing Haipeng 'walks' silkworms aboard Tiangong-2.
Somewhat confusing matters, Zhang Yulin, deputy commander-in-chief of China's human spaceflight programme, also stated this week that the Long March 5B would launch for the first time in 2019, suggesting a later schedule than announced by others.
"The research and production of the new rocket specially used to launch the space station will be based on Long March 5. There are still some challenges and more research work will be carried out...It will launch the space station in 2019," Zhang said.
Constructing a space station
Bao Weimin, also of CASC, told press earlier this week that from 2018 to completion, the CSS project will require more than a dozen launches, including launching modules, Tianzhou cargo vessels and Shenzhou crewed missions to the facility.
Liu Yang, China's first woman in space, said in an interview this week that the country's astronauts are in training for extravehicular activities - EVAs or 'spacewalks' - and maintenance of the CSS.
Above: A model of the CSS with a Shenzhou vessel docked below and Tianzhou craft (fore) on display during China's first space day in April 2016.
Two experiment modules named 'Wentian' and 'Mengtian' will join with Tianhe-1 to form the CSS. Smooth progress would see it completed by around 2022.
The two science modules will feature experiment racks focusing on the areas of space life sciences and biotechnology, microgravity fluid physics and combustion, material science in space, fundamental physics in microgravity and other multi-purpose uses.
Above: Space life science experiment racks for the CSS (CMSA).
The CSS will feature two 30-metre solar panels and two robotic arms for construction, repair and docking.
Also expected to be part of the CSS is a free-flying space telescope with a two-metre mirror, dubbed 'China's Hubble'.
The Xuntian module is expected to provide a level of resolution no less than the famous Hubble space telescope, but with a field of view 300 times larger.
Above: An illustration of China's Xuntian space telescope.
China began its human spaceflight programme in 1992, and in 2003 became only the third country after the United States and Russia (Soviet Union) to independently put an astronaut - namely Yang Liwei - in space,
The CSS is the ultimate goal of 'Project 921', which China aims to keep permanently crewed with 3-6 astronauts for at least a decade.
Above: Tianzhou-1 undergoing testing at the AIT centre in Tianjin, North China (CGTN/Framegrab).