What goes up, must come down.
An out-of-control Chinese space lab the size of a bus is expected to fall to Earth within days, according to the latest estimate from the European Space Agency (ESA), which is monitoring its descent.
Tiangong-1, China’s first space station, was launched in 2011 and has been in decreasing orbit ever since. In 2017, China admitted it no longer had control of the space station.
The ESA’s Space Debris Office said that the re-entry window for the Tiangong-1 space station was between March 30 and April 2 although it warned the estimate was “highly variable.”
The China Manned Space Engineering Office said it expects the lab to reenter the atmosphere between March 31 and April 4, burning up in the process.
Experts say the potential danger to humans is small. The odds of debris from the lab hitting a human are less than one in 1 trillion. That compares to the one-in-1.4 million chance of being struck by lightning.
However, China’s secrecy around the space mission is making it hard for experts to properly assess the risks involved in the fiery descent.
“The international community doesn’t know what the craft is made of, and that makes estimating the danger more challenging, as hardened fuel containers could reach the ground while lightweight panels won’t,” said Alan Duffy, a research fellow at the Centre for Astrophysics and Supercomputer at Swinburne University of Technology in Australia.
Current predictions show the lab re-entering as early as March 29, and as late as April 2.
Experts said it’s difficult to establish exactly where the space lab will fall, but it’s expected to descend within a latitude of 43 degrees north and south of the equator.
In the U.S., the highest probability of debris impact is located on a narrow horizontal band bisecting the country. These areas include Oregon, northern California, parts of Nevada, Idaho, Utah, Colorado, Wyoming, Nebraska, Iowa, Minnesota, Wisconsin, Illinois, Indiana, Ohio, Pennsylvania, New York, New Jersey and Connecticut. Even then, the risk isn’t that high at all.
Markus Dolensky, the technical director at the International Centre for Radio Astronomy Research in Australia, said if skies were clear witnesses may potentially see a “series of fireballs streaking across the sky.”
The last human space outpost to fall to Earth was the 135-ton Russian space station Mir in 2001. That was a controlled landing, with most parts burning up upon return and the rest landing in the ocean.