After six years of service in testing systems for a future larger space station, China’s prototype station dubbed “Heavenly Palace” will fall back to Earth sometime in 2017. There’s one problem, however: Scientists can’t tell you when it will happen, or where it will land when it comes crashing down.
The Tiangong-1 laboratory has orbited our planet at about 370 kilometers from the Earth’s surface. But such a high orbit is unsustainable, and space officials say it is starting to decay. They will continue to monitor the orbit despite not controlling its descent.
According to the state-run Xinhua News Agency, officials expect most of Tiangong-1 to burn up upon re-entry. That said, some pieces may make it to the ground, and Wu Ping, deputy director of the manned space engineering office, said the country would issue warnings internationally if necessary.
At 10.4 meters long and nearly 8.75 tons, Tiangong-1 served as a testbed for a variety of critical systems, such as life support. It also docked with the Shenzhou-8, Shenzhou-9, and Shenzhou-10 spacecrafts and performed a variety of other tasks during its four-and-a-half-year lifespan, some two years longer than initially anticipated.
Decommissioned officially in March, Tiangong-1 was replaced by Tiangong-2 which launched last Thursday. The new station will house two Chinese astronauts in October or early November for up to a month, which will perform further tests on life support systems and “scientific research.” One of those tests is an atomic clock, which scientists want to use to determine if the effects of gravity increase the accuracy of the timepiece, according to news reports.
But even Tiagong-2 won’t stay in orbit very look. That station, too, will fall to earth in an uncontrolled manner, likely soon before the final version of the station launches sometime in the 2020s.