Are solar power satellites sitting ducks for orbital debris?
The Russian stakes for cooperation to remove orbital debris
Most of the large orbital debris is Russian, including over 70% of the total mass in LEO. US-Russia relations have fallen to another nadir. The relationship is filled with the growing suspicion and mutual hostility harkening back to the Cold War. So why would Russia cooperate with the United States (and others) to deal with orbital debris?
First, those Russian debris pieces, large and small, carry with them liability under the 1972 Liability Convention. Second, the debris represents enormous value in an emerging economic model for space debris cleanup, both as already emplaced highly refined metal and buses for enabling nanosats. Third, the US Department of State, in coordination with the UN Committee on the Peaceful Uses of Outer Space (COPUOS), could play crucial role in putting together an agreement between Russia and the United States to remove the 79% of the orbital debris with the greatest shrapnel-generating potential. Fourth, this heritage of Russian space debris may provide a strategic opportunity for Russia to enhance its international position in the commercial development of space.
Sweating the small stuff: what about the shrapnel?
To remove small debris, “laser nudging” from ground-based lasers appears to be the most viable option. In this concept, a powerful ground-based laser would ablate the front surface off a debris target to slow and thereby deorbit it. To remove the political-military element, the system would have to be ground-based, transparent, and under international civilian control. In this regard, several observers have proposed an international civilian consortium to manage, in transparent fashion, ground-based lasers targeting debris shrapnel smaller than 10 centimeters for ablation to induce deorbiting.34 Under such a regimen, consensus would be needed to select targets and timing for deorbiting. A bounty system could also be used to facilitate commercial participation so that the consortium members need not pay for complex and expensive development project, or for failures, but only for results.35 A system paying bounties for results could also be used to facilitate the removal of large debris.
Along with property rights in space, international laws and treaties touching on the delicate issue of lasers to remove orbital debris will eventually have to be modified. The prestigious Institute of Air and Space Law of McGill University has recently proposed a meeting to carry out just such considerations.36
Shrapnel-tracking improvements are crucial
When it comes to using lasers to deorbit debris, beyond having to organize a large group space-involved countries and getting their consensus, there is another major problem standing in the way: small orbital debris is currently not being tracked, and even larger debris is not tracked in real-time.37
Doug Beason, Senior Vice President for Special Programs at the Universities Space Research Association, decries the lack of tracking of the most immediately dangerous shrapnel, i.e. debris larger than five millimeters but smaller than ten centimeters. He suggests public-private efforts to “find, fix, track, and target” orbital debris objects, so they can be engaged and that engagement later be assessed.38 Also, because the Joint Space Operations Center is part of US Strategic Command, much of its tracking technology is secret. According to Beason, an international station with optical, radar, and polarization debris-tracking technologies under civilian control is urgently needed, not to find and track sensitive satellites, but to find and track in real-time, orbital debris, including shrapnel
Instead of depending on military debris detection and tracking wrapped in secret capabilities and protocols, international investment in a transparent non-military commercial tracking system is needed. We have transitioned from a military-only GPS system to commercial dependence on GPS tracking that now includes Russian GLONASS and European Galileo systems, in addition to Chinese and Indian positioning systems. We can make the same type of transition with orbital debris tracking systems.
“Free parking” orbits as commercial disincentives to risk reduction
Beyond remediation, steps can be taken to mitigate orbital debris as well. Joe Carroll decries the 25-year “free parking,” which results from international guidelines for satellite companies to deorbit their satellites after 25 years of non-use.39 Technology already exists that can begin deorbiting a satellite the moment it stops functioning. In this regard, the company Tethers Unlimited has developed a conductive “terminator tape,” which uncoils out of a defunct satellite, causing both aerodynamic and electrodynamic drag to deorbit the spacecraft. Two of the company’s terminator tapes are currently being tested as demonstrators on CubeSats.40
On the other side of the ocean, the European Space Agency (ESA), in coordination with the University of Surrey, is about to test the de-orbiting capabilities of the pop-out five-by-five-meter gossamer solar sail technology it developed.41 Other countries and institutions are developing debris mitigation and remediation technologies based on grab-and-plunge spacecraft, solar sails, electro-static nets, and balloons.42
The risk of generating hundreds of millions of dollars of damage from orbital debris collisions is currently not properly balanced against the costs of deorbiting or moving satellites. An economic model creating disincentives for extending the risk-time of zombie satellites is needed and is another topic for consideration of new space laws and treaty provisions. At present, we have not developed the mix of carrots and sticks needed for an effective economic model.
Pay now or pay (much more) later43
There is an old adage that “a stitch in time, saves nine.” In the spirit of this saying, we should note that if no action is taken to address orbital debris until there are multi-level Kessler cascades, the tab will be much higher than now in terms of direct financial costs for satellite insurance, satellite replacement, and satellite service disruption in various industries and businesses. Therefore, nearly all persons living in industrialized societies will eventually have to pay the tab one way or another, if in no other way, through increased user fees.
If the voluntary “seed money” and bond schemes mentioned above (under “The Risk Avoidance-Insurance/ISRU Industrial Start-up Model”) are not instituted, it might fall to the international space-users community to empower the International Telecommunications Satellite Organization (ITSO) to collect a universal and mandatory tax on satellite services to finance bounties to be paid to commercial entities for orbital debris remediation. For such a plan to work, all satellite-service providers would have to contribute (i.e. no “free riders”), so that no competitive advantage would exist from non-compliance.
Orbital debris: resource ladder to the stars
Not only is orbital debris the “low hanging fruit” with regard to a vast supply of already refined metal and emplaced structures on which to hang empowering nanosats, the technologies that will be developed to deal with debris, will also be useful for dealing with capturing and mining near-Earth asteroids (NEOs),44 lunar mining, on-orbit assembly of spacecraft, robotic transport of materials, and other technologies. Growing out of a commitment to remove, recycle, or rehabilitate orbital debris could come new cislunar industries, including materials reprocessing, spacecraft manufacturing, multi-purpose platform construction, propellant depots and staging site construction, cislunar transportation development, new communication networks, and navigation infrastructure.
The issue raised by the consideration of solar power satellites as sitting ducks is merely illustrative of the risks and reward of both present and future economic activities. It also raises the issue of international legal reforms and new initiatives. Space debris could be a show stopper for the future—but only if we let it. It is well within our power to constructively address the risks and investments to facilitate an emergent, and eventually booming, cislunar space ecosphere.
The investment to manage and remediate space debris is first an “insurance” cost to maintain acceptable levels of risk in doing space-connected business. Remediating orbital debris is also the road to a vibrant cislunar economy. The emerging cislunar economy will include solar power satellites, GEO communications platforms, Earth-Moon Lagrange facilities, and a reusable transportation infrastructure in cislunar space and will be orders of magnitude greater than the current space economy. Solving the challenges of orbital debris opens the door to that greater economy.