Paul Seideman / Los Angeles

Increasing use of small satellites is creating a potential space debris issue that needs to be addressed by bringing them back into the atmosphere to be destroyed on re-entry, according to Robert Twiggs, consulting professor at Stanford University’s Department of Aeronautics and Astronautics.

“Depending upon orbital altitude, these satellites can remain in space for as much as 100 years,” Twiggs said at the International Space Development Conference in Los Angeles, California last week. “We don’t want them up there that long.”

Small spacecraft ranging from microsatellites weighing up to 100kg (220lb) to picosats of under 1kg offer lower launch costs, and they can be deployed with larger payloads on an excess-capacity basis. As many as 50 small satellites are estimated to have been launched since the 1960s.

Twiggs said two re-entry technologies are being examined. One is a tether that would pass through the Earth’s magnetic field, converting the orbiting satellite’s momentum to electrical energy and dissipating that energy as heat. The second is an expendable device that would be deployed to increase the satellite’s atmospheric drag. “The problem is, how do we put this device into something this small?” he said, adding a solution is likely to be developed in the next two to three years.

Source: Flight International