Tiangong-1, China’s out-of-control space station, has finally made its way back to Earth. The station entered Earth’s atmosphere and landed over the Pacific Ocean on April 1st. Tiangong-1 has been in orbit for the last seven years. The space station has dominated news headlines in the last few weeks as experts tried to estimate and predict where exactly it was going to land. This wasn’t easy but it was already known that the risk to hit somebody was very low.
The out-of-control space station was a dense and heavy vehicle. Because of its size, there were several experts who thought that some pieces of it could survive re-entry into the Earth’s atmosphere. Despite this, it was highly unlikely that the Tiangong-1 would cause any harm to humans. A number of factors combined to make sure of this. First, 71% of Earth’s surface is ocean and most of the land is unpopulated. With these facts in mind, the chances of getting hit by falling debris from a space station are one in 1 trillion.
The Tiangong-1 space station was launched back in 2011. It was the first human space station created by China. During its time in orbit, there were two crew visits including a maiden trip for the first female Chinese astronaut. The Chinese space agency didn’t consider the Tiangong-1 as a long-term space station. In fact, the initial plan was to have it in orbit for a couple of years, and then a more advanced Tiangong-2 would be launched.
However, China extended Tiangong-1’s time in orbit as it bought more time to successfully complete the development of the Tiangong-2. In 2016, China notified the UN that it had lost control of the space station. While the Tiangong-1 was coming down, the Chinese space agency had no power to control its movement. A lot of concerns were raised due to the massive size of the space station that weighed about 18,740 pounds.
Nonetheless, this wasn’t the first time that satellites and rocket pieces have fallen back to Earth uncontrolled. The Russian Zenit rocket that was heavier than the Tiangong-1 also came down on free fall early this year. In 2011, the Russian spacecraft Phobos-Grunt weighing almost double the Tiangong-1 fell back to Earth uncontrolled without causing any harm. But the biggest and heaviest object to fall from space uncontrolled was NASA’s old space station Skylab. Weighing nearly 160,000 pounds, the Skylab fell from space uncontrolled in 1979.
Tiangong-1’s return back to Earth now makes way for the deployment of the Tiangong-2 as China advances its space program to catch up with other countries. Just like Tiangong-1, the Tiangong-2 is also not made for long-term operations in orbit but it’s very likely that it will last longer than its predecessor.