Harriet Brettle, Posted on:16 July 2021 – Categories: Space surveillance and tracking
As space becomes busier and critical orbits become increasingly crowded, there is a pressing need to ensure the safe and sustainable use of the outer space environment.
At the recent G7 summit in Cornwall, G7 nations published a joint statement committing to the safe and sustainable use of space in recognition of the growing hazard of space debris and increasing congestion in Earth’s orbit. This proliferation of space debris leads to higher risks and increased costs for satellite operators individually, as well to the environment holistically.
Addressing the requirement to return environments back to their natural state is not without precedent on Earth. Industries on Earth already consider how to deal with assets that pose a danger to the environment once they have reached the end of their operational life. The process, known collectively as decommissioning, is undertaken across the oil and gas, nuclear and offshore wind industries.
Putting this in a space context, we consider decommissioning to include removing satellites from operational service and returning the environment of Earth’s protected orbits to its natural state, through either re-entry into the Earth’s atmosphere or moving satellites to a graveyard orbit.
Decommissioning can be undertaken either using a satellite’s own propulsion capabilities, outsourcing to third party debris removal services, or through passive decay for satellites operating at very low altitudes.
The complexity, and therefore cost, of satellite decommissioning may vary dramatically depending on the asset’s health and capabilities at the time of decommissioning. In practice, satellites are not always decommissioned and can remain in critical orbits for many decades. The case for decommissioning is clear. It can:
- protect the orbital environment and safety for increasing human activity in orbit
- mitigate costs that satellite operators are burdened with as a result of operating in a polluted environment
- reduce collision risk, debris creation, and ultimately reduce the number of objects that could incur liabilities for space-active nations.