On the agenda of the United Nations Committee on the Peaceful Uses of Outer Space meeting currently being held in Vienna is the increasingly urgent problem of space debris.

As US deputy assistant secretary for space and defence policy Frank Rose outlined at the International Institute of Strategic Studies in London, where he stopped to brief journalists on his way to Austria, there has been a "massive spike" in the amount of debris in the past five years.

With the global economy and security increasingly reliant on orbiting assets, the time is now for international action to prevent further degradation of the space environment.

The US Department of Defense tracks some 22,000 pieces of debris larger than 10cm, and estimates there are hundreds of thousands of smaller pieces it cannot see. But, as Rose notes, at 9,450kt (17,500 km/h) even one of those smaller pieces would cause catastrophic damage to a spacecraft, or even the space station.

More than a third of the debris being tracked stems from two recent incidents: a 2007 Chinese anti-satellite weapon test that left 3,500 large pieces at about 2,620,000ft (800,000m), where Rose says they will remain for hundreds of years, and a 2009 collision between a defunct Russian military satellite and an Iridium communications satellite.

Rose underscores the urgency of the situation by warning that a couple more such incidents could very well close much of low-Earth orbit to spacecraft.

The US took advantage of its G8 presidency to raise the debris issue at the group's recent Camp David summit, and Rose sees the Vienna meeting as a chance to build further momentum towards agreement by all space players to avoid "irresponsible acts". A European proposal from 2010, he adds, could form the basis of a sound agreement if it can be built into a widely supported code of conduct.

Source: Flight International