Ever wondered if anyone controls where satellites are launched into space? The answer to this: yes!! Since 1976, the regulatory body for objects sent into space is the United Nations. Responsibility for the maintenance of a register of objects – and that any planned launches are sufficiently separated – lies with the United Nations Office for Outer Space Affairs.
To date, over 86 per cent of all satellites, probes, landers and crewed spacecraft launched into Earth orbitor beyondhave been registered with the UN. Those that haven’t generally predate 1976.
The latest numbers show that there are about 6,250 satellites in Earth orbit, of which about 3,900 are still operating.ButEarth’s space environment is populated with a further 28,210 pieces of ‘space junk’ and up to 129 million smaller fragments that can’t be tracked. Such material is monitored optically or with radar by various agencies, often as members of the Inter-Agency Space Debris Coordination Committee.
Even so, satellite operators are finding itharderto avoid the potential for catastrophic collisions. In 2009, satellites Iridium 33 and Kosmos 2251 collided above Siberia, whilethe latest near-miss happened on 9 April 2021 when a US meteorological satellite passed within an estimated 21m of part of a Soviet rocket launched in 1971.
Furthermore, some experts warn that a ‘critical mass’ of space junk may be only a few decades away. This is where one major collision results in an uncontrollable chain reaction.
Although it may be possible to gather or destroy space debris, it seems likely that some form of ‘space traffic control’ may soon be required – and that future satellites will include autonomous collision avoidance systems.
Read more:
- Why does the Earth spin?
- What are the chances of being hit by falling space junk?
- The Earth’s rotation is changing speed: should we be worried?
- Are space launches bad for the environment?
Asked by: Ian Holden
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