You’ve probably seen the news this week that China successfully launched the first piece of what will become a brand new space station. The module was launched on Thursday and China used one of its powerful Long March 5B rockets to push the hardware skyward. It was a big day for China’s space agency, and it got a lot of attention. Unfortunately, one of the factoids that wasn’t part of the initial buzz was the fact that China has no way of controlling its rocket stage that is now orbiting Earth and slowly falling back toward the surface.
As SpaceNews reports, the core stage of the Long March 5B that sent the “Heavenly Harmony” space station module into orbit is now tumbling around our planet. The uncontrolled rocket component is absolutely huge and it won’t be long before the pull of gravity becomes too much and it falls through the atmosphere back toward us. Where will the pieces land? Nobody has any idea.
Rocket stages that send satellites or other spacecraft into orbit around Earth regularly end up falling back toward Earth. In the vast majority of cases, the rocket stages fall into predictable areas, usually in the ocean. Some launches result in rocket stages reaching speeds that would allow them to orbit Earth, but those are often controlled using burns that force them to slow down and, again, tumble harmlessly into the ocean or burn up in the atmosphere. In many cases, the hardware can’t withstand the intense friction of reentry and is essentially vaporized.
In the case of China’s Long March 5B, the rocket reached orbital velocity but will have a limited amount of time before it is dragged back down. China does not seem to have employed a controlled burn feature, making the rocket very unpredictable. Its size will make it the single largest uncontrolled spacecraft to reenter the atmosphere, and it’s possible that enough of the rocket stage will survive reentry and impact the ground below.
So, there’s a big rocket flying around above our heads and at some point over the next week or so it’s going to come down… somewhere. It’s moving extremely fast, completing an orbit of Earth every 90 minutes or so, and that makes predicting its reentry location close to impossible. Should we be freaking out? Eh, probably not.
The rocket will indeed burn up in the atmosphere and the majority of it should be completely destroyed in the process. It’s possible that no debris even survives reentry, but if it does, it’s likely going to come down in the ocean. Earth has more ocean than anything else and the odds of the debris coming down on land is relatively small. Smaller still are the odds of it impacting a populated area, and if we want to get really technical, the odds of it actually hitting someone or causing an injury is very, very, very small. It’s not zero, but it’s pretty close.