A scale model of China’s Tiangong-1 space station. Jason Lee/Reuters
- In 2016, China lost control of its first space station, called Tiangong-1 or “Heavenly Palace.”
- The Aerospace Corporation expects the spacecraft to burn up in Earth’s atmosphere in mid-March, give or take a couple of weeks.
- Chunks of the 8.5-ton vessel should be durable enough to reach our planet’s surface.
- Any surviving pieces of Tiangong-1 will most likely land in the ocean.
China’s first space station, called Tiangong-1 or “Heavenly Palace,” will soon explode over Earth into a rain of fiery debris.
Aerospace Corporation, a nonprofit research company, predicted last month that the derelict spacecraft would reenter Earth’s atmosphere in mid-March, give or take two weeks — so possibly as early as the end of February or as late as April.
When it does, extreme heat and pressure caused by plowing through the air at more than 15,000 mph will destroy the 8.5-ton vessel.
Not everything may vanish, though.
There’s a good chance that gear and hardware left on board could survive intact all the way to the ground, according to Bill Ailor, an aerospace engineer who specializes in atmospheric reentry. That durability is thanks to Tiangong-1’s onion-like layers of protective material.
“The thing about a space station is that it’s typically got things on the inside,” Ailor, who works for Aerospace Corporation, previously told Business Insider. “So basically, the heating will just strip these various layers off. If you’ve got enough layers, a lot of the energy is gone before a particular object falls out, it doesn’t get hot, and it lands on the ground.”
For example, he said, after NASA’s Columbia space shuttle broke up over the US in 2003, investigators recovered a working flight computer — an artifact that ultimately helped explain how the deadly incident happened.
Predicting Tiangong-1’s crash to Earth
Tiangong-1 is a two-room space station for two taikonauts, or Chinese astronauts. It has a volume of 15 cubic meters, about 1/60th of the football-field-size International Space Station.
Though China superseded Tiangong-1 in 2016 with Tiangong-2, space experts hailed it as a major achievement for the nation’s space program, since it helped pioneer a permanent Chinese presence in orbit.
“It conducted six successive rendezvous and dockings with spacecraft Shenzhou-8, Shenzhou-9, and Shenzhou-10 and completed all assigned missions, making important contributions to China’s manned space exploration activities,” said a memo China submitted in May to the United Nations Committee on the Peaceful Uses of Outer Space.
An illustration of Tiangong-1, China’s first space station, orbiting Earth. China Manned Space Agency
In the memo, China said it lost contact with the spacecraft on March 16, 2016, after it “fully fulfilled its historic mission.”
By May 2017, Tiangong-1 was coasting about 218 miles above Earth and dropping by about 525 feet a day, the memo said. Its altitude has since plummeted to less than 175 miles, according to Aerospace Corporation data.
“For any vehicle like this, the thing that brings them down is atmospheric drag,” Ailor said. “Why there’s a lot of uncertainty in the predictions is that it depends on what the sun’s doing, to a large measure.”
The sun can unleash solar storms and solar flares — bursts of X-rays and ultraviolet light — that heat Earth’s outer atmosphere, causing the air to expand and rise. That forces low-flying objects like Tiangong-1 to plow through denser gases.
“This puts just a little bit of a higher force on these objects that causes them to come down,” Ailor said.
An analysis of the combined effects of solar activity and Tiangong-1’s orbital speed, direction, and altitude, as well as other factors, helped the Aerospace Corporation provide its most recent estimate of a mid-March de-orbit. Before the big moment, however, the company may refine its estimate as conditions change.
What will happen when China’s space station is destroyed
An illustration of Europe’s ATV spacecraft breaking apart and burning up as it reenters Earth’s atmosphere.ESA/D. Ducros
Tiangong-1 is likely to crash over the ocean, as water covers about 71% of Earth’s surface. But there’s a decent chance some pieces may strike land as it breaks up over a long and thin oval footprint.
“The whole footprint length for something like this could be 1,000 miles or so,” Ailor said, with heavier pieces at the front and lighter debris toward the back.
If anyone is lucky enough to witness Tiangong-1’s atmospheric breakup from an airplane, it may look similar to the destruction of the European Space Agency’s 14-ton Automated Transfer Vehicle — an expendable spacecraft that was once used to resupply the ISS.
When asked for comment on Tiangong-1’s threat to ongoing NASA missions, the space agency told Business Insider it “actually doesn’t track any debris.”
Ailor says pieces of China’s space station are “really unlikely” to hit anyone or anything on Earth.
“It’s not impossible, but since the beginning of the space age … a woman who was brushed on the shoulder in Oklahoma is the only one we’re aware of who’s been touched by a piece of space debris,” he said.
Should a hunk of titanium, a computer, or another piece smash through a roof or windshield, however, international space law covers compensation for victims.
“It’s China’s responsibility if someone gets hurt or property gets damaged by this,” NASA’s representative said.