Detecting Debris in Space


Just last week we wrote about the International Space Station needing to manuever to dodge junk in space — or, specifically, the debris from the disused satellite that the Chinese recently shot down in a military experiment.

Thus it’s a bit ironic, as NewScientistSpace points out, to learn that the "only experiment designed to survey and trace the origin of space debris too tiny to be tracked by radar has been cancelled:"

An international team of scientists had been planning to capture and catalogue this dust from outside the International Space Station with an experiment called LAD-C (Large Area Debris Collector). Meant to be launched on a shuttle in 2008, LAD-C was going to catch the debris in a sponge-like aerogel mounted on a 10-square-metre aluminium grid.

When a piece of space debris hit the aerogel, it would have sent vibrations along the metal grid, where piezo sensors similar to the ones in electronic drum kits would have picked up the signal.

A computer would have registered the location, impact speed and timing of the strike, and based on the orientation of the space station, this would have given the particle’s orbital trajectory. Researchers would then know whether it came from space junk, an asteroid or a comet, and would be able to study its composition when the experiment was brought back to Earth in 2009…

The cancellation of LAD-C collector (additional details of which can be found here, in this PDF) comes at a strange time, NewScientist argues:

The cancellation coincides with the most dangerous orbital debris event in the history of space launches. On 11 January, China destroyed one of its own weather satellites with a ground-launched ballistic missile, creating more than 900 objects larger than 10 cm across and an estimated 35,000 smaller objects spanning at least 1 cm. The debris spread throughout low-Earth orbit, from altitudes of 200 to nearly 4000 kilometres, and is expected to stay in space for hundreds of thousands of years. 

Without the LAD-C, how will rocket scientists keep up with all the debris in space?

Why, by reading the Orbital Debris Quarterly, of course.

Meanwhile, this rockets scientist has been told by his supervisor (at home, not in the office) that our own personal LAD-C is operational and should in fact be deployed.