China's defunct Tiangong 1 space station mostly burned up on re-entry Monday into the atmosphere over the central South Pacific, Chinese space authorities said.
The experimental space laboratory re-entered around 8:15am, the China Manned Space Engineering Office said.
Scientists monitoring the craft's disintegrating orbit had forecast the craft would mostly burn up and would pose only the slightest of risks to people. Analysis from the Beijing Aerospace Control Center showed it had mostly burned up.
Brad Tucker, an astrophysicist at Australian National University, said Tiangong 1's re-entry was "mostly successful" and that it would have been better if the space station had not been spinning toward Earth.
"It could have been better obviously, if it wasn't tumbling, but it landed in the Southern Pacific Ocean and that's kind of where you hope it would land," Tucker said.
"It's been tumbling and spinning for a while, which means that when it really starts to come down it's less predictable about what happens to it," Tucker said. He likened it to an airplane landing, saying it's more difficult to predict where a plane that is "shaking around and moving" will land than one that is smoothly descending.
Launched in 2011, Tiangong 1 was China's first space station, serving as an experimental platform for bigger projects, such as the Tiangong 2 launched in September 2016 and a future permanent Chinese space station.
Two crews of Chinese astronauts lived on the station while testing docking procedures and other operations. Its last crew departed in 2013 and contact with it was cut in 2016.
Since then, it has orbited gradually closer and closer to Earth on its own while being monitored.
Earlier forecasts had said only about 10 percent of the bus-sized, 8.5-ton spacecraft would likely survive re-entry, mainly its heavier components such as its engines.
"The biggest takeaway from this is that as we put more things into space, all countries, we have to be aware that we do have to plan for these sorts of issues that are happening," Tucker said.
Debris from satellites, space launches and the International Space Station enters the atmosphere every few months, but only one person is known to have been hit by any of it: American woman Lottie Williams, who was struck but not injured by a falling piece of a US Delta II rocket while exercising in an Oklahoma park in 1997.
Most famously, America's 77-ton Skylab crashed through the atmosphere in 1979, spreading pieces of wreckage near the southwestern Australia city of Perth, which fined the US $400 for littering.