China recently launched a Long March-5B Y2 rocket into space that carried its first space station module into orbit. Although China hailed the launch as a complete success, it turns out that something went wrong. The rocket’s 21-ton central stage is expected to make an uncontrolled re-entry into the Earth’s atmosphere in the coming days.
An uncontrolled reentry has the potential to cause debris to fall into populated areas, posing a risk to property and lives on the ground. The rocket should fall at a designated location in the ocean, which is common for discarded rockets. However, instead of desorbing as planned, the rocket continues to orbit the planet out of control.
Authorities say the rocket is expected to fall back to Earth in the next few days. Astronomer Jonathan McDowell, who tracks objects orbiting the Earth, said that it is unacceptable to let an object enter again without control by current standards. He also pointed out that, since 1990, nothing more than 10 tons has been deliberately left in orbit in an uncontrolled manner. The Chinese rocket measures 30 meters long and 5 meters wide.
According to McDowell, it can burn entirely in the Earth’s atmosphere when it exits orbit. However, there is a chance that large pieces of rubble will survive the re-entry. Most of the planet is made up of the ocean, so the rocket is more likely to impact water, but it can threaten inhabited areas.
Holger Krag, head of ESA’s Space Safety Program Office, said it is difficult to assess the amount of surviving mass and the number of fragments that could be created without knowing the rocket’s design. However, he said a reasonable rule of thumb is that about 20 to 40 percent of its original dry mass could survive re-entry. The rocket has the potential to impact a large area of the Earth, with large cities well within the impact zone, including New York, Madrid and Beijing, among others.