This Harpoon Could Lasso Space Junk To A Fiery End

A massive dead satellite is lurking in the space around Earth. Envisat, a 9-ton hunk of space junk, is just one of many pieces of debris plaguing our planet's cluttered orbit.

But engineers in Stevenage, U.K. are on a mission to destroy it, the BBC reports.

Airbus, a company best-known for its commercial airplanes, is building a three-foot-long harpoon which could, in theory, puncture Envisat and drag it to the Earth's atmosphere where it would face a fiery anihilation.

The team are designing their space junk harpoon with this satellite in mind because it is such a big target. "If we can design a harpoon that can cope with Envisat, then it should be able to cope with all other types of spacecraft including the many rocket upper-stages that remain in orbit," advanced project engineer Alastair Wayman told the BBC.

Airbus has been testing the harpoon at its Stevenage facility. A gas gun fires the harpoon into thick, metal panels "like a hot knife through butter," Wayman said. Then, barbs unfurl and lodge the harpoon in place.

In space, a tether would de-tumble the satellite, aided by thrusters that would bring the satellite under control.

Wayman believes the harpoon could work better than other methods proposed to clear up bits of space junk. "Many of these targets will be tumbling and if you were to use a robotic arm, say, that involves a lot of quite complex motions to follow your target," he said.

With a harpoon, you can just sit, wait and fire at the opportune moment. When a particular satellite target is set, harpoon operators would have a pretty good idea of where to strike to avoid hitting something potentially dangerous like a pressurized tank, Wayman explained.

The European Space Agency—which operated Envisat—is developing a number of concepts to clean up space, including releasing a satellite-catching net. Next month, a demonstration satellite designed by the U.K.'s Surrey Satellite Technology will trial a net system in space on the RemoveDebris mission. A small Airbus harpoon will go along for the ride to test its performance in weightless space.