Earlier this year, signs appeared that China was reshuffling its Tiangong space laboratory program. The first Tiangong lab module was launched in 2011, and two astronaut crews lived aboard it. The Tiangong 1 laboratory has now completed its mission of demonstrating the basic technologies required for a space station and is expected to re-enter any time now.
China's original plan called for three Tiangong laboratories, with the next ones each successively more advanced than its predecessor. Tiangong 3 would be the final step before China launched the first module of the Chinese Space Station, a large modular structure that should be completed around 2020.
The plan sounded logical. China would steadily improve its capabilities for a permanent base in space, just as it had steadily improved its Shenzhou crew-carrying spacecraft. Then changes appeared in media reports and technical presentations. As has happened before, China did not explicitly spell out its plans, and analysts were forced to try to make sense of a rough collage of facts and figures.
After a conference presentation by China's first astronaut, this analyst (and others) concluded that China had telescoped the Tiangong program. It seemed that China would delete the intermediate-stage Tiangong 2 module and go straight for the advanced Tiangong 3, which would now be re-branded as the new Tiangong 2.
There could have been good reason for this. Tiangong 1 was highly successful, and China could have decided that their technology was ready for a larger step. Deleting an intermediate module would save time and money for the program. Such a revised program made sense and it was easy to accept that this would happen.
Now, this analyst is highly confused about what is really happening with the Tiangong program. And so are other analysts outside of China. Will there be one or two more Tiangongs? What will they (or it) be like? How many docking ports will they (or it) have? Will there be refueling experiments with a cargo vessel? All of these questions are being asked, but it's hard to obtain or even deduce solid answers.
There have been intriguing reports and video clips circulating in the Chinese media. But the recent International Astronautical Congress in Beijing failed to clear up the confusion about their program. The more material circulated, the less clear the situation becomes. Why all the uncertainty?
This analyst is beginning to believe that there's a simpler explanation for the Tiangong reshuffle. The Chinese themselves are still revising their plans and haven't settled on a final outcome.
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