Space debris surrounds Earth.

More than half a million pieces of man-made debris are orbiting Earth, posing a threat to future manned space missions.

Illustrative image.

According to Tech Insider, the amount of debris sent into space by humans has been increasing since the first satellite was launched into orbit in the late 1950s. The video above was created by Stuart Grey, a lecturer at the University of London and a member of the UK Space Navigation and Measurement Laboratory, and uploaded to YouTube on December 20th.

Space debris accumulates because we don't clean it up. Instead of recovering defunct satellites and bringing them back to Earth, humans often leave them out in space, putting them at risk of collisions with asteroids or other man-made debris traveling at speeds of around 27,000 km/h.

At that speed, a collision would shatter the satellite into hundreds of smaller pieces. These fragments are attracted by Earth's gravity, causing them to orbit the planet. In this way, they accumulate to over half a million pieces of debris, endangering manned space missions.

"The only way to solve this is to recover the large objects," Donald Kessler, head of NASA's space debris program, stated in 2013.

In September of this year, he once again emphasized the need to quickly recover anything humans send into space, otherwise, when large objects in space reach a "critical density," they will collide and create more debris than humans can recover.

According to VnExpress