China Uses Drag Sail to Clear Up Space Junk Successfully

Chinese space scientists have said they successfully used a huge space sail to remove debris from Earth's orbit.

Announced by the Shanghai Academy of Spaceflight Technology on July 6, the huge sail was launched and was successfully used to deorbit the Long March 2 rocket.

The sail is made from an incredibly thin membrane, one-tenth the diameter of a human hair, and measures around 270 square feet. When attached to the Long March 2 rocket, it served to increase the atmospheric drag acting on the rocket, accelerating the process of orbital decay and removing it from orbit faster.

According to Interesting Engineering, the sail's material is low-cost, flexible and lightweight, meaning that it can easily be produced and launched to remove any form of space debris from orbit.

Of the nearly 5,000 satellites still in orbit around the Earth, only around 2,000 remain operational, meaning that the rest is now classified as space junk. There are also up to 27,000 smaller pieces of debris also being tracked by NASA, clogging up the orbit zone and traveling extremely fast—15,700 mph in low-Earth orbit. The more things we send into orbit, the more likely they are to collide, which in turn creates a huge number of extra chunks of space debris. In 2009, a defunct Russian craft collided with a U.S. Iridium commercial spacecraft, adding 2,300 pieces of large, trackable debris and countless more smaller debris to the already busy orbit.

space junk
Stock image of space debris orbiting the Earth. The drag sail is designed to speed up the removal of space junk from orbit. iStock / Getty Images Plus

Space junk has the potential to be deadly in future space missions. While small chunks of debris floating around far away may not seem like much of a problem, in March 2022, a fast-moving piece of a Chinese rocket smashed into the surface of the moon. If it had hit the International Space Station (ISS) instead, it could have been catastrophic. The ISS has had to perform 25 maneuvers since 1999 in order to avoid being hit by oncoming debris. Even if space junk hit something that humans didn't live on, it could still have dramatic consequences as we rely on satellites for a huge number of things, from communication and navigation to search and rescue and weather monitoring.

While eventually everything in orbit around the Earth will eventually fall to the ground once an orbit decays naturally, this can take a very long time, especially if they are orbiting far away from the Earth. Space junk in high-Earth orbit, around 22,000 miles out, may take hundreds, or even thousands, of years to fall back to Earth. This sail technology aims to enable the orbital decay process to be accelerated, meaning that we can get rid of debris from orbit faster and hopefully ensure the safety of future spacecraft and astronauts.