China's manned space programme is preparing for another decisive step forward — the launch of its first outpost in space, the Tiangong-1. This orbiting space laboratory and its two successors will test hardware and provide the operational experience needed for the country to put up a full-fledged space station by around 2020.
Media reports have indicated that the Tiangong-1, a name that translates as “Heavenly Palace,” could be launched by an improved Long March 2F rocket from the Jiuquan Satellite Launch Centre (JSLC) in north-west China at the end of August. However, the recent failure of a Long March 2C rocket carrying an experimental satellite has given rise to rumours that the launch might be postponed.
In 2003, China became the third nation capable of sending humans into space when Yang Liwei circled the earth for about 21 hours in the Shenzhou-5 capsule. Two years later, two of its astronauts stayed aloft in the Shenzhou-6 for nearly five days. That was followed by a three-day mission by three men aboard the Shenzhou-7 in 2008, one of whom came out of the capsule and carried out a spacewalk.
Right from 1987, when the Chinese government came up with “Plan 863-2” for the development of the space sector, a space station in low earth orbit was set as the goal for its human space flight programme, according to Gregory Kulacki of the U.S.-based Union of Concerned Scientists and Jeffrey Lewis, currently with the Monterey Institute of International Studies in California.
A place in space
The Chinese aerospace experts on the committee that developed the plan decided that such a space station would be one of the hallmarks of a twenty-first century great power. “A country with the capability of claiming and holding a long-term place in space would signal international significance and national strength,” Dr. Kulacki and Dr. Lewis observed out in their book on the Chinese space programme.
The Tiangong-1, along with the Tiangong-2 and -3 that are to follow, will be vital stepping stones towards that objective. Much as the Salyuts did for the Soviet Union in the 1970s and 1980s and the Skylab for the U.S. in 1970s, the Tiangongs will provide China with hands-on experience in docking spacecraft, maintaining crew in space and keeping a space laboratory going.
Indeed, the path that the Chinese have chosen to follow resembles that of the Soviet Union, which launched a series of smaller Salyut stations before going on to assemble the much larger Mir space station.
The eight-tonne Tiangong-1 will have two modules. The larger one, which the Chinese have called the “experiment module,” will be here the astronauts live and, as its name suggests, carry out various experiments. The other, which has been termed the “resource module,” will house support systems, including the solar arrays that supply the electricity required by on-board equipment.
Docking of spacecraft
China's goal is to realise the docking of two spacecraft during the second half of 2011, declared Mr. Yang Liwei, now deputy head of the China Manned Space Engineering office, at a press conference earlier this year.
The Tiangong-1 will have two docking ports, one at each end of the spacecraft, according to information published by the office on its website.
The plan is to first launch the space lab and then send an unmanned Shenzhou-8 to automatically dock with it. Such docking is essential for periodically sending crews and supplies to an orbiting space laboratory or station. That capability will also be needed for assembling the large space station that China wants to establish by early next decade, which will have multiple modules that are launched separately.
The Soviet Union first demonstrated automatic docking between two spacecraft in October 1967 and repeated it again the following year.
Despite this experience, several early manned Soyuz capsules had difficulties in automatically docking with Salyut stations.
If the Shenzhou-8 is successful, then two manned missions are likely to follow next year. The Shenzhou-9 could have a three-person male crew while the Shenzhou-10 could see two men and a woman going to the space lab, according to Brian Harvey, an Ireland-based space analyst who has published a book on the Chinese space programme.
The ‘Tiangong' series
Although the Tiangong-1 is expected to remain operational for about two years, it will not, unlike the Mir and now the International Space Station, be continuously occupied.
The Chinese had not disclosed how long the Shenzhou-9 and -10 missions would last, Mr. Harvey told this correspondent. However, it was thought that these missions could each be about 10 days to 20 days in duration.
Subsequent Tiangongs were likely to see increasingly longer missions, as happened with the later Salyut stations of the Soviet Union. The Chinese were also working on a cargo version of the Shenzhou, which would allow the astronauts to stay aboard a space station for extended periods of time, he said.
“An important part of the thinking of Tiangong is that it will carry scientific experiments that are man-tended from time to time and can be left to operate automatically in between visits,” he added.
China's progress in manned spaceflight was “very impressive,” remarked Phillip S. Clark, a British expert on the Chinese programme.
“The speed and capabilities of China's manned programme are often derided but on their fourth manned flight the Chinese aim to complete orbital docking and transfer to a space lab,” he pointed out in a recent posting on a forum at the space website NASASpaceFlight.com.
Space station
For China, the goal is to build a 60-tonne space station made up of different modules. Earlier this year, the public were asked to suggest names for the space station, which is to be completed around 2020.
The core module of the station, weighing of 20 tonnes to 22 tonnes, will be launched first. Two smaller laboratory modules will then be linked to the core module. A manned spaceship as well as a supply vessel can be docked to the space station.
In order to launch modules of the 20-tonne class, the Long March 5 rocket, which is under development, has to become operational. The rocket will also be used to send a sample-return mission to the Moon.
China currently anticipates completing its space station in the early years of the next decade, which, coincidentally, is about the time that the International Space Station is scheduled to be decommissioned, observed Dr. Kulacki on the blog All Things Nuclear.
“If both those things happen, China's space station will become the de-facto new international space station,” he pointed out.
