China’s Tiangong-1 space lab fell to Earth Monday, landing in the Southern Pacific Ocean, following weeks of speculation over where and exactly when the craft would re-enter the atmosphere. The lab broke apart on entering the atmosphere, according to CNN. While the crash was expected, the European Space Agency had assured the public that the craft would likely break up above water, which covers the majority of the Earth’s surface, and that the likelihood of being hit by debris was “10 million times smaller than the yearly chance of being hit by lightning.”
“This is a big thing the size of a school bus. Most of the stuff in it will just burn up in the atmosphere,” said American Museum of Natural History astrophysics curator Mordecai-Mark Mac Low.
Only ten percent of the craft was expected to survive through reentry.
According to Jonathan McDowell, an astrophysicist from the Harvard-Smithsonian Center for Astrophysics:
“It did exactly what it was expected to do; the predictions, at least the past 24 hours’ ones, were spot on; and as expected it fell somewhere empty and did no damage.”
A total of thirteen space agencies were monitoring the space lab’s trajectory around the word, using radar and optical observation.
China told the United Nations in 2017 that the lab had “ceased functioning,” while providing little explanation as to why. It was launched in 2011, as a stepping stone toward China’s long-term goal of launching a permanent space station by 2022. The lab was last occupied by astronauts in 2013. China launched a second space lab, the Tiangong-2, in 2016.
The nation has also developed a heavy-lift rocket, called the Long March 5, for launching the core-module of a permanent station into orbit.
Normally, a craft such as the Tiangong module would have undergone a more controlled re-entry process, with thrusters positioning the object above a remote area of the Southern Ocean. In this case, command links had apparently been lost, preventing a more controlled re-entry process. However, uncontrolled re-entries are not unprecedented, and the 10 meter (32 foot) long space lab is far from the largest craft to undergo such a re-entry.
At 74 tons, the first US space station, the Skylab, underwent an uncontrolled re-entry in 1979. It reentered the atmosphere safely, with debris scattering over western Australia. Nothing was damaged and no one was harmed, but Australia fined the US $400 for littering.
According to McDowell, Tiangong may be the 50th largest craft to undergo uncontrolled re-entry.