Chinese engineers are developing tow sails to reduce space debris

Did you know that around 8,950 satellites have been put into orbit to date? According to the latest estimates, about 5,000 of these satellites remain in orbit, although they have reached the end of their lives and are no longer serving a purpose.

The growing problem of space debris

It is estimated that only about 1,950 of these satellites are still operational, while the rest have become space junk. Joining these now-defunct satellites are thousands of pieces of debris collectively known as “space debris.”

And this junk is a huge problem because there is currently no way to safely get this junk out of space. Until now.

On Wednesday, the Shanghai Academy of Spaceflight Technology announced that Chinese scientists have successfully deployed a tow sail to bring a recently launched Long March 2 rocket out of orbit. The event marked the first time such an experiment was conducted on a rocket.

The tow sail is a kite-like membrane that measures 25 square meters (269 square feet) when fully deployed. It’s also just a tenth the diameter of a human hair thick, which didn’t stop it from increasing atmospheric drag and accelerating orbital decay of the 300 kg (661 lb) rocket’s final stage.

Towed sails offer a cost-effective and mature technology solution that can be used on any type of low-Earth satellite that has become space debris. Because they are very flexible and light, they can be folded into a small package and placed on a spacecraft before launch.

Once they get close to the debris, they automatically deploy and help send the spacecraft back into the atmosphere, where it dissipates. Tow sails are a much faster option than allowing scrap to deorbit naturally, which can take years or decades.

China’s space debris problem

It is fitting that China finds a solution to this ongoing problem as the nation has been accused of allowing many of its ships to pollute space. As early as March 2022, part of a Chinese space rocket floating aimlessly through space, believed to have taken part in an October 2014 launch, hit the moon.

Fortunately, no one was injured in the collision, but the debris could have done significant damage as it headed toward the International Space Station.

Meanwhile, in November 2021, a group of mechanical engineers led by University of Utah Professor Jake J. Abbott developed a new space debris disposal plan that uses spinning magnets to manipulate orbital debris, making it easier to handle and collect. The new concept relied on exposing debris to a changing magnetic field, causing electrons to circulate in charged loops within the metal debris.