Even the most finely engineered machines such as satellites eventually reach the end of their functional lives.
There are about 1,000 operational satellites in orbit around the earth. Added to this is an array of various types of space junk.
In the early days of space travel no one really gave much thought to the problems that would be posed by so much material orbiting the earth; however there is now a considerable risk both in terms of launching new spacecraft and possible damage to existing assets.
The issue of what to do with old satellites and spacecraft that have reached the end of their lives has never been so important. So what happens to them when they “die”? There are basically three possible fates.
For satellites that are closer to earth their last remaining fuel loads can be used to slow their trajectory so that they re-enter the earth’s atmosphere.
If they are a smaller object the friction of the atmosphere will cause them to burn up on re-entry and that is the end of them.
Larger objects which may not completely burn up are directed by operators towards a place in a very remote part of the South Pacific nicknamed the “spacecraft graveyard”. This area is the final resting place of the debris of large numbers of spacecraft.
The third fate for satellites that are in higher orbits is to use the remaining fuel load to push them further away from the earth into a “graveyard orbit”. For satellites that are in these higher orbits it can take more fuel to slow them sufficiently to effect re-entry, than to push them further away. This orbit is at least 200 miles further than the farthest operational satellites some 22,400 miles above earth.
The “graveyard orbit” is very much like a celestial version of a “boneyard”. Non-functional spacecraft float through space facing an as yet uncertain fate. For the moment it is not an issue but it may become more problematic with the huge increase in satellite numbers expected over coming years.
Spacecraft operators conform to an international regulatory suite which covers state and private operators and for now this allows the “graveyard orbit” to be a viable option, but there is some concern about what happens as this area becomes increasingly crowded.
One day it may become necessary and viable to operate a space garbage collection service but for now they wait silently in their “graveyard”.
VIDEO: A look at the graveyard orbits in space from Scott Manley’s YouTube channel.
