It's a green light for the first mission to remove large space debris orbiting the Earth.

The European Space Agency and Swiss startup ClearSpace SA will launch the ClearSpace-1 demonstration mission in 2025. The $102 million deal will be the first "active debris removal mission" to remove space junk whizzing around the Earth at hundreds of kilometers per hour.

It will deploy a net that will collapse onto and capture a modular dispenser that launches satellites into orbit.

In December, the agency and ClearSpace experts will give an overview of the project status.

The agency is funding the 2025 mission and contributing experts. Lessons learned will be applied to its Active Debris Removal/In-Orbit Servicing project.

Luisa Innocenti, who heads the agency's Clean Space initiative, said the world needed to develop technologies to avoid creating new debris and remove the debris already up there.

"NASA and agency studies show that the only way to stabilize the orbital environment is to actively remove large debris items," Innocenti said.

"Accordingly we will be continuing our development of essential guidance, navigation and control technologies and rendezvous and capture methods through ADRIOS. The results will be applied to ClearSpace-1. This new mission, implemented by an agency project team, will allow us to demonstrate these technologies - achieving a world first in the process."

The agency says there are more than 750,000 objects in orbit with a size larger than 1 centimeter - all of which pose potential threats to manned and unmanned satellites. These objects coexist with around 3,000 inactive satellites out of 4,500 orbiting the Earth. Every year, some 100 tons of debris reenters the Earth's atmosphere.

The most effective way to put an end to these collisions - that create more debris - and stabilize the debris in critical orbits is to remove it.