Debris from Chinese rocket on collision course with Earth expected to crash this weekend

China recently launched the Long March 5B rocket, carrying the 22.5 tonne Tianhe module, as part of the country's plan to start its own space station.

According to SpaceNews.com, "the Long March 5B uniquely uses a core stage and four side boosters to place its payload directly into low Earth orbit." While the Tianhe module successfully separated and entered its planned orbit, the core of the Long March 5B rocket mistakenly entered orbit as well.

"Most expendable rocket first stages do not reach orbital velocity and reenter the atmosphere and land in a pre-defined reentry zone", SpaceNews.com reports, however the Long March 5B rocket is "tumbling and thus not under control."

In an interview with Fox News, Dr. Jonathan McDowell, an astronomer at the Harvard-Smithsonian Center for Astrophysics, stated that the core is travelling at speeds of 18,000 mph "relatively horizontally" around Earth. As the orbit shrinks "due to friction with the atmosphere", the core continues to heat up.

"Eventually", said Dr. McDowell, "it gets low enough that the drag on it just gets way, way bigger very quickly. And, instead of continuing to orbit it just sort of plummets down and as it plummets down it gets even hotter." He added that as this happens, "the thing breaks apart into a bunch of shrapnel."

This is not the first time the launch of one of China's Long March 5B rockets has ended with shrapnel falling to Earth. Last May, "a 12 meter long object crashed into the village of Mahounou in Cote d'Ivoire."

When asked whether people should be afraid of flying or "standing in a particular spot on the Earth", McDowell replied, "Here's the thing, you've got to stand somewhere." He added that the fact that the core is travelling so fast means there's "no way that you can predict the re-entry time accurately enough to predict the re-entry location in a useful way."