'Janitor satellite' cleans up space junkyard

A team of Swiss scientists hope to become pioneers in the effort to mop-up our orbit and prevent satellites and 'spacejunk' colliding.

An $11 million project designed to clear up space debris is underway by Swiss scientists.

The Swiss Space Center at EPFL is close to launching CleanSpace One, a project dedicated to building the first satellite prototypes designed to 'de-orbit' and clean up the debris we leave in our space system.

Space debris is a menace for spacecraft and active satellites. It can cause accidental impacts, ensure enormous costs for replacements to be launched, and generate even more debris once active machines and its disused predecessors collide -- spreading even more spacejunk through Earth's orbit. The debris can include decommissioned satellites, broken spacecraft, spent rocket stages and fragments left from previous impacts of machines.

An example of a collision is that of the 2009 U.S. satellite Iridium-33 explosion upon impact with the abandoned Russian satellite Cosmos-2251. Not only did it further exacerbate the problem by adding to our collection of space debris, the estimated costs to insure existing machines against such impacts is now approximately $20 billion.

"It has become essential to be aware of the existence of this debris and the risks that are run by its proliferation," says Claude Nicollier, astronaut and EPFL professor -- as the presence of debris makes space research projects and satellite control more difficult.

NASA manages to track approximately 16,000 pieces of debris, but is hampered as it can only monitor the largest ones (a minimum 10cm in diameter). However, at the 17,000-mph speed debris travels, even a single bolt or fingernail-sized scrap of metal can cause serious damage to a window or panel on a shuttle. Last year, the Swiss Re insurance company published a report stating that there is a one in 10,000 chance that a 10 m2 satellite will collide with such debris. Facing these odds, it's no wonder space insurance is rocketing in price. The International Space Station has to constantly adjust its orbit in an attempt to avoid such debris.

As with all space-related projects, it won't be plain sailing to get the cleaners up in to orbit. After launch, the satellite will have to adjust its trajectory to match its target's orbital plane, grab it, and de-orbit at high speed -- especially problematic if the spacejunk is rotating. The cleanup satellite will be travelling at 28,000 km/h at an altitude of 630-750 km.

The scientists are planning to introduce a gripping mechanism, which will allow CleanSpace One to 'de-orbit' the offending item by heading back into the atmosphere, where both will burn up.

The team hope to become part of the cleanup effort within three to five years. The Swiss scientists have chosen a 'symbolic' target for the first space mop-up -- either Switzerland's first orbiting object, the Swisscube picosatellite, or its cousin TIsat.

Swiss Space Center Director Volker Gass explains:

"We want to offer and sell a whole family of ready-made systems, designed as sustainably as possible, that are able to de-orbit several different kinds of satellites. Space agencies are increasingly finding it necessary to take into consideration and prepare for the elimination of the stuff they’re sending into space. We want to be the pioneers in this area."

For more information, see the video below.

Image credit: EPFL


This post was originally published on Smartplanet.com