Southampton researchers have developed the world's first robust method for estimating the value and mass of space junk.

A fully circular economy for space—removing space junk and reusing or recycling it—is a viable possibility to safeguard the future for satellites and space exploration, according to new research from the University of Southampton.

The research estimates there is billions, potentially trillions, of dollars' worth of recyclable materials, in the form of space junk (mission debris and defunct satellites), orbiting the Earth. Knowing what is 'out there' will enable viable solutions to the growing problem to be effectively and justifiably pursued.

Space junk is a form of pollution that poses a threat to future space exploration and satellites—which we rely heavily on here on Earth.

As of January 2021, the US Space Surveillance Network reported 21,901 artificial objects in orbit around Earth, including almost 4,500 functioning satellites. But these are just the objects large enough to be tracked. There is also estimated to be more than 128 million pieces of debris smaller than 1cm, more than 900,000 pieces measuring 1cm to 10cm, and 34,000 pieces larger than 10cm.