§ Lord Kennetasked Her Majesty's Government:
What is their estimate of the number of useless objects currently in orbit around the earth; how many present risks to useful objects; and what steps are being taken to retrieve them to reduce garbage in space. [HL2644]
§ The Parliamentary Under-Secretary of State, Department of Trade and Industry (Lord Sainsbury of Turville)The population of catalogued manmade objects in orbit around the earth is approaching 10,000. This number represents objects greater in size than about 30crn in low earth orbit (LEO) and greater than about 1 metre in geosynchronous earth orbit (GEO). Of these catalogued objects, only about 350 are active satellites. In addition, there are estimated to be over 300,000 objects in orbit that are greater than 1 cm and a correspondingly larger number of even smaller objects. Natural debris predominates at sizes less than 1mm, man-made debris at all other sizes.
All objects in earth orbit present some element of risk to active space systems. The extent of the risk depends on the orbit.
The UN Committee on the Peaceful Uses of Outer Space (COPUOS) is working towards agreement on the steps to be taken to mitigate the growth and impact of space debris. A report will be submitted to the UN General Assembly in Autumn 1999. Recommended activity includes removing space objects from orbit at the end of their lives, making safe objects remaining in space and other measures to help control the rate of growth of space debris.
The European Space Agency (ESA) has also recently produced a Space Debris Mitigation Handbook which will be presented to industry in early June.