The U.S. government tracks 500,000 chunks and bits of space junk as they hurtle around Earth. Some 20,000 of these objects are larger than a softball.

To clean up the growing mess, scientists at the University of Surrey have previously tested a net to catch chunks of debris. Now, they've successfully tested out a harpoon.

The video below, released Friday by the university's space center, shows a test of the experimental RemoveDEBRIS satellite as it unleashes a harpoon at a piece of solar panel, held out on a 1.5-meter boom.

The harpoon clearly impales its target.

“This is RemoveDEBRIS’ most demanding experiment and the fact that it was a success is testament to all involved," Guglielmo Aglietti, director of the Surrey Space Centre at the University of Surrey, said in a statement.

Next, the RemoveDEBRIS team — made up of a group of international collaborators — is planning its final experiment: responsibly destroying the satellite.

In March, the RemoveDEBRIS satellite will "inflate a sail that will drag the satellite into Earth’s atmosphere where it will be destroyed," the university said a statement. This is how the group intends to vaporize the future dangerous debris it catches.

Human space debris hurtles around Earth faster than a speeding bullet, with debris often traveling at 17,500 mph, or faster. The threat of collisions is always present, though in some orbits the odds of an impact are significantly lower than others. The International Space Station, for instance, is in a relatively debris-free orbit, but even here there is the threat of "natural debris" — micrometeors — pummeling the space station.

Other orbits have considerably more debris spinning around Earth. In 2009, a derelict Russian satellite slammed into a functional Iridium telecommunication satellite at 26,000 mph, resulting in an estimated 200,000 bits of debris. In 2007, the Chinese launched a missile at an old weather satellite, spraying shrapnel into Earth's orbit.

This risk amplifies as more satellites are rocketed into space. SpaceX now has government-approved plans to launch thousands of its Starlink satellites into orbit — perhaps by the mid-2020's, should they amass money for the pricey program.

This would double or triple the number of satellites in orbit.

"The sheer number, that’s the problem."

"It is unprecedented,” said Kessler, NASA's former senior scientist for orbital debris research told Mashable. "The sheer number, that’s the problem."

Kessler has long warned about the potential of catastrophic chain reactions in Earth's orbit, wherein one collision creates enough weaponized debris to create a cycle of destruction.

Designs to harpoon dangerous chunks of debris are just being tested in space today, but the technology could prove critical as Earth's orbit grows increasingly trafficked with large, metallic satellites.