The European Space Agency sets its sights on harpooning space debris

In 2021, as part of its Clean Space Initiative, ESA plans to launch the e.DeOrbit mission. The aim of this mission is to clean up the important polar orbits between altitudes of 800 to 1,000 km (500 to 625 mil) that face the prospect of becoming unusable due to the increasing buildup of space debris.
The ESA has now announced plans to examine the potential for the mission to use space harpoons to capture large items, such as derelict satellites and the upper stages of rockets. The ESA has previously revealed it is considering a number of approaches to meet the challenge of capturing and securing space debris. These include snaring the debris in a net, securing it with clamping mechanisms, or grabbing hold of it using robotic arms. Another option is a tethered harpoon, which would pierce the debris with a high-energy impact before reeling it in.
Such an approach wouldn’t be applicable for smaller debris, but is aimed at reeling in uncontrolled multitonne objects that threaten to fragment when colliding with other objects, resulting in debris clouds that would steadily increase in density due to the Kessler syndrome.