EUSO telescope

An international team of scientists led by Japan’s Riken institute is planning to trial a telescope and laser system on the International Space Station (ISS) to clear space debris.

Scientists plan to use the super-wide field-of-view Euso (Extreme Universe Space Observatory) telescope and the Can laser system to track and de-orbit space debris around the size of one centimetre.

The high power laser beams shot on the debris will produce plasma ablation, which will reduce the orbital velocity of the debris, leading it to re-enter Earth’s atmosphere, the team said.

The Euso telescope is designed to evaluate ultraviolet light emitted from air showers that are produced by cosmic rays entering the atmosphere.

Riken computational astrophysics laboratory chief scientist Toshikazu Ebisuzaki said: "During twilight, thanks to Euso’s wide field of view and powerful optics, we could adapt it to the new mission of detecting high-velocity debris in orbit near the ISS."

Featuring bundles of optical fibres, the Can laser is designed to power particle accelerators, and is said to achieve high-power and a high repetition rate.

"We could create a free-flyer mission and put it into a polar orbit at an altitude near 800km, where the greatest concentration of debris is found."

At the ISS trial, scientists will use a 20cm version of the Euso telescope and a laser with 100 fibres.

Ebisuzaki added: "If that goes well, we plan to install a full-scale version on the ISS, incorporating a 3m telescope and a laser with 10,000 fibres, giving it the ability to de-orbit debris with a range of approximately 100km.

"Looking further to the future, we could create a free-flyer mission and put it into a polar orbit at an altitude near 800km, where the greatest concentration of debris is found."

Space debris comprises artificial objects orbiting the earth, including derelict satellites, rocket bodies and small fragments produced by collisions between debris.

From 2000 to 2014, the number of junk objects in space is said to have doubled and the total mass of space debris is estimated at around 3,000t.

Image: The team plans to use the field-of-view Euso telescope and the Can laser system, to track and de-orbit space debris. Photo: courtesy of Riken / AlphaGalileo.