Garbage trucks in space
Kessler syndrome has become an ever increasing threat not only to astronauts, but to a general satellites. It has been recognized as a general problem, but (due to international aspect) there is no agreement that defines who will pay for the cleanup business.
Therefore individual governments take passive approach, by requiring new space deployments to provide plans for 25-year deorbiting life of any LEO asset. But that is "soft requirement" that does not address problems of hardware disintegration that is happening in all orbits.
Large satellite constellations will be increasingly affected by such processes, as it will have cascading effects and is becoming a threat to their operations. In commercial world, such risks are covered by insurance. Therefore insurers have inherent interest in reducing major operational risks for spacecraft. So far, this risk was dominated by launch risk failures. But for constellations, higher launch rates and increasing launch reliability reduce this risk. On the other hand, in-orbit failures are likely to increase due to the Kessler syndrome.
So is it possible that major satellite operators or insurers will "self-tax" without pressures of their governments? That is not likely. But each space power will have inherent interest to subsidize its space industry to perform cleanup of their assets. The only likely exception is Russia, due to their dwindling budget and huge amount of space artifacts launched during Soviet era. Other space powers could request permission to deorbit Russian assets, but that might cause issues with Russian national interest and pride.
So far, only viable deorbiting scenario is orbital rendezvous with uncooperative target.
Due to large delta-V, long coast time in orbit, it could perform several deorbiting runs in a single mission, without major development cost.
So garbage collection has potential to become very profitable business in space. While very low orbits have "self-cleaning" capabilities, increasing density of particles in higher orbits (together with massive LEO constellations), will require coordinated cleanup effort on international level.
In previous post, I have proposed Dragon tug derivative, that would be capable of 6km/s delta-V. That is enough to reach GEO from LEO, and then reduce it to GTO, which would be used to perform reentry. Using robotic hand, Dragon tug would be able to perform rendezvous and capture failed GEO satellite and push it to graveyard orbit. It can perform this operation for several satellites, cleaning up the GEO and reducing risk for operational satellites.
But BFR would be capable of similar feat, while staying fully reusable and promising lower cost per mission. It would be much more useful for de-orbiting large pieces present in LEO and MEO, where it would be also capable of performing multiple deorbit runs for artifacts in similar orbital planes. For example, reducing periapsis from circular 800km orbit to 800x200km orbit can cause reentry in months by using 200m/s delta-V. After most of the fuel is spent, BFR would reenter and land for refurnishment and refueling.
If we assume 50 million USD for mission cost, that would bring clean-up cost per object to less than 5 million USD if only ten items are captured and deorbited. So just half a billion per year would remove 100 large objects and 100t from LEO per year (three Iridium constellations each year). Such a large sum would also be ideal extension of the COTS approach enabling other commercial space companies to compete for such missions. Other space agencies could also participate by "swapping" rights to deorbit satellites, rocket stages and debris in similar orbits or even trading that for provision of satellite services and payloads. For example, ESA and EU are very active in pursuing space debris cleanup, despite their relatively small percentage of space debris compared to USA and Russia. Common cleanup efforts could use BFR as launcher and base for proximity operations, while ESA would provide satellites and devices for performing rendezvous and capture of uncooperative targets. Then BFR would provide orbital changes needed for putting a target debris towards early atmospheric entry. By using international cooperation and non-American capture technology, military aspects and repercussions of such technology would be greatly reduced. Frequent and repeatable BFR launches would also enable test-bed for different and exotic capture technologies.
Therefore individual governments take passive approach, by requiring new space deployments to provide plans for 25-year deorbiting life of any LEO asset. But that is "soft requirement" that does not address problems of hardware disintegration that is happening in all orbits.
Large satellite constellations will be increasingly affected by such processes, as it will have cascading effects and is becoming a threat to their operations. In commercial world, such risks are covered by insurance. Therefore insurers have inherent interest in reducing major operational risks for spacecraft. So far, this risk was dominated by launch risk failures. But for constellations, higher launch rates and increasing launch reliability reduce this risk. On the other hand, in-orbit failures are likely to increase due to the Kessler syndrome.
So is it possible that major satellite operators or insurers will "self-tax" without pressures of their governments? That is not likely. But each space power will have inherent interest to subsidize its space industry to perform cleanup of their assets. The only likely exception is Russia, due to their dwindling budget and huge amount of space artifacts launched during Soviet era. Other space powers could request permission to deorbit Russian assets, but that might cause issues with Russian national interest and pride.
So far, only viable deorbiting scenario is orbital rendezvous with uncooperative target.
Due to large delta-V, long coast time in orbit, it could perform several deorbiting runs in a single mission, without major development cost.
So garbage collection has potential to become very profitable business in space. While very low orbits have "self-cleaning" capabilities, increasing density of particles in higher orbits (together with massive LEO constellations), will require coordinated cleanup effort on international level.
In previous post, I have proposed Dragon tug derivative, that would be capable of 6km/s delta-V. That is enough to reach GEO from LEO, and then reduce it to GTO, which would be used to perform reentry. Using robotic hand, Dragon tug would be able to perform rendezvous and capture failed GEO satellite and push it to graveyard orbit. It can perform this operation for several satellites, cleaning up the GEO and reducing risk for operational satellites.
But BFR would be capable of similar feat, while staying fully reusable and promising lower cost per mission. It would be much more useful for de-orbiting large pieces present in LEO and MEO, where it would be also capable of performing multiple deorbit runs for artifacts in similar orbital planes. For example, reducing periapsis from circular 800km orbit to 800x200km orbit can cause reentry in months by using 200m/s delta-V. After most of the fuel is spent, BFR would reenter and land for refurnishment and refueling.
If we assume 50 million USD for mission cost, that would bring clean-up cost per object to less than 5 million USD if only ten items are captured and deorbited. So just half a billion per year would remove 100 large objects and 100t from LEO per year (three Iridium constellations each year). Such a large sum would also be ideal extension of the COTS approach enabling other commercial space companies to compete for such missions. Other space agencies could also participate by "swapping" rights to deorbit satellites, rocket stages and debris in similar orbits or even trading that for provision of satellite services and payloads. For example, ESA and EU are very active in pursuing space debris cleanup, despite their relatively small percentage of space debris compared to USA and Russia. Common cleanup efforts could use BFR as launcher and base for proximity operations, while ESA would provide satellites and devices for performing rendezvous and capture of uncooperative targets. Then BFR would provide orbital changes needed for putting a target debris towards early atmospheric entry. By using international cooperation and non-American capture technology, military aspects and repercussions of such technology would be greatly reduced. Frequent and repeatable BFR launches would also enable test-bed for different and exotic capture technologies.
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