It has been eight years since the Soviet nuclear- powered spy satellite Cosmos 954 crashed in northern Canada, alerting the world to the dangers of putting nuclear reactors into space. But despite U.S. President Carter's subsequent call for a ban on nuclear materials in orbit and despite a similar Canadian initiative leading to drawn out diplomatic wranglings at the U.N., increasing numbers of nuclear satellites still seem destined to be launched. In the U.S., a new generation of larger reactors for space is under development, the first of which could be ready to be Shuttled into orbit by the early 1990's.
Though NASA envisions many uses for the new reactors -- from rocket propulsion to baseload power for space factories -- it is the military that has kept their development alive. Through its Strategic Defence Initiative Organization, set up to fund "Star Wars" research into President Reagan's "non-nuclear defensive shield", the Department of Defense has agreed to pay half the $300 million projected cost of designing, building, and ground testing the new reactor by 1991. SDIO sees nuclear reactors as a promising source of power for future space weapons. Whether or not a "Star Wars" defense ever gets built, planned SDI research will result in more nuclear reactors in space.
The disintegration of Cosmos 954 over the Northwest Territories on Jan. 24, 1978, thrust the issue of nuclear powered satellites (NPS) into the political spotlight. For the first several weeks the story assumed dramatic proportions, as nightly newscasts pictured the airborne and ground search and recovery operations set against a backdrop of sub-arctic winter. CBC camera crews were aboard as Hercules aircraft, specially outfitted with radiation sensors, criss-crossed the frozen wilderness looking for "hot spots". Parka-clad decontamination teams trudged through the snow to locate radioactive bits of the downed satellite and to package and remove them in specially shielded cannisters. Helicopters, snowmobiles, even dog-teams played their parts in "Operation Morning Light", as the joint Canada-U.S. clean-up effort came to be known.
Operation Morning Light continued into October and eventually resulted, according to Canada's Atomic Energy Control Board (AECB), in the estimated recovery of 0.1 percent of Cosmos 954's nuclear core. (1) Tens of millions of pepper-flake sized radioactive particles, comprising a fifth to a quarter of the core, remained scattered over a 124,000 square kilometer "footprint" (2), stretching southward from Great Slave Lake into northern Saskatchewan and Alberta. The clean-up of these from populated and frequented areas and the recovery of a number of large satellite fragments from the more remote bush cost Canada nearly $14,000,000 (2), of which only $3,000,000 was later recovered from the USSR. (3) Obviously a far more comprehensive clean-up would have been deemed necessary had Cosmos 954 come down over a large city or a major agricultural region like the prairie wheat belt to the south, over which the satellite in fact flew on its penultimate orbit.
Within a week after the Cosmos crash, U.S. President Carter called for "an agreement with the Soviets to prohibit earth-orbiting satellites with atomic radiation material in them." (4) Two weeks later, Canadian Minister for External Affairs Don Jamieson sent up his own a trial balloon about "some kind of nuclear-free zone in near outer space," (5) and Canada proposed establishment at the U.N. of a working group of technical experts to look into the whole question of nuclear powered satellites. (6, 7) Sweden called for a moratorium on NPS launchings while the working group was to deliberate (7).
The Soviet Union, however, staunchly refused to recognize any need for new principles governing nuclear power in space and, at first, tried to block discussions at the U.N. (8, 9) But by July of 1978, due to the pressure of almost unanimous agreement among non-East-bloc nations, the Soviets relented and agreed to the establishment of a working group. (10) Without acknowledging any need for new rules or accepting responsibility for Cosmos 954, the Soviet Union, five months after the crash, finally admitted that the subject of nuclear power sources in space was at least important enough to talk about.
In November of the same year, the General Assembly authorized its Committee on the Peaceful Uses of Outer Space (UNCOPUOS) to establish a technical working group. The assembly also passed a resolution requesting that a country whose NPS is about to fall notify others of the impending danger. (11) Though this was a step forward (in view of the fact that the U.S., and not the USSR, had first warned Canada about Cosmos 954), it is the only substantive resolution on NPS the General Assembly has yet adopted.
The newly established working group had no difficulty agreeing in principle that "NPS can be used safely in outer space, provided that all necessary safety requirements are met." (12) Unfortunately, to this day there has been only vague consensus among the national delegations as to what should constitute "necessary safety requirements", and the agreement in principle is purely rhetorical.
Arguments have persisted at the U.N. over whether safety regulations regarding nuclear power in space should be mandatory or voluntary, or whether they are even needed at all. And much disagreement remains about what the proposed rules should include. For example, should countries planning to launch nuclear powered satellites be obliged to give prior notification to other nations? Both superpowers have repeatedly resisted proposals by Canada, Sweden, Denmark, West Germany and others for some form of international notification before or at time of NPS launch. (13, 36) President Carter's early call for a ban on nuclear materials in space has never been repeated, and the Americans, like the Soviets, appear to be keeping their options open for secret military nuclear missions in space.
The U.S. space nuclear program has always had close ties and even owes its existence to the military. Officially "terminated" in the mid 1970's after expenditure of more than $1.4 billion for lack of concrete NASA mission requirements, the program was revived and re-funded as a result of Air Force interest in new power sources for space-based radar. (14)
Today, the U.S. is developing, according to a Department of Energy (DOE) press release, "a compact nuclear power system that will provide a safe and highly reliable source of hundreds of kilowatts of electric power for a broad range of civilian and military space applications, including the Strategic Defense Initiative, in the early to mid-1990's and beyond." (15) This joint project of DOE, SDIO, and NASA, which got underway in 1983, has moved into its $300 million second phase: construction and ground testing of the new "SP-100" reactor by 1991 at the Hanford nuclear reservation in Washington state. (16) The SP-100 will be designed to be carried aloft in the cargo bay of the Space Shuttle and to generate 300 kilowatts of electricity in space. (17, 18) DOE and SDIO are splitting the cost of phase two, with NASA playing an advisory role until the later, flight phases. (19) According to a senior DOE official involved with the program, "All the near term applications are military." (20)
In comparison, the largest U.S. power supply ever flown in space was Skylab's 12 kilowatt solar cell array in 1973. Soviet nuclear Radar Ocean Reconnaissance Satellites (RORSATs) like Cosmos 954 or Cosmos 1402 (which disintegrated over the South Atlantic in 1983) reportedly have used up to 20 kilowatts of electricity. (21) A typical large earthborne commercial power reactor, on the other hand, generates several hundred thousand kilowatts, while SDI ultimately might require an amount of energy equal to "a substantial fraction of the output of the eastern U.S. power grid," according to one SDI official. (22)
Some 50 spacecraft carrying nuclear power sources (either bona fide nuclear fission reactors, or less powerful "radioisotope thermoelectric generators" powered by the decay heat of plutonium) have been launched by the superpowers. Of these, at least eight have come down unexpectedly over various parts of the earth. (23, 30) One was a U.S. navigational satellite which in 1964 failed to achieve orbit and dispersed its entire plutonium-238 inventory into the stratosphere above the Indian Ocean. This incident alone resulted in a near tripling of the global fallout of Pu-238. (24)
Another radioisotope power pack, this one from the lunar module of the aborted Apollo 13 moon-landing mission, lies intact at the bottom of the 6-km deep Tonga Trench in the South Pacific, where it fell from the sky in 1970. (25, 26, 30) A number of major American space successes, including the Apollo moonshots and the Voyager unmanned missions to the outer planets, have relied on radiosotope power sources. Until the recent Challenger disaster postponed all NASA's plans, a plutonium power pack was scheduled for May 1986 launch via Space Shuttle as part of the Galileo probe to orbit the planet Jupiter. (26, 27)
The only U.S. satellite thus far to carry a nuclear fission reactor failed in 1965 after 43 days aloft and was subsequently boosted into a 4000-year orbit in order that its radioactivity might have time to decay to safer levels before it descends to earth. (23, 28, 29) Injection into higher orbit is the method of reactor "disposal" preferred by both the American and Soviet programs. (26, 29, 30) Both the Cosmos 954 and Cosmos 1402 accidents are blamed on failures of the rocket systems that should have boosted these satellites into long-lived orbits. (26)
Most of the concern expressed at the U.N. has focussed on NPS in low orbits of less than 300 to 500 years duration, too short for fission products to decay away sufficiently. The U.S.'s SP-100 Program, accordingly, has adopted the policy of not operating the reactor unless it is in a stable orbit with at least a 300 year life span (more than 520 kilometers high). (26) However, it isn't yet clear at what altitude the military will want to operate its nuclear-powered Star Wars battle stations. And, like the Soviets, whose nuclear RORSATs are shot into orbits only 240 kilometers high, the Americans are studying how to engineer the controlled breakup of satellites during re-entry from low orbit should booster systems fail. (26, 29)
The official U.S. "Nuclear Safety Criteria and Specifications for Space Nuclear Reactors" (31) allow for "short-lived orbit missions" so long as a "reentry core dispersal capability" is provided, apparently to ensure that no large radioactive fragments reach the ground intact. This contrasts with Canada's position at the U.N. that "in principle ... nuclear reactors should not be used in low earth orbit." (32)
Regarding the best form of dispersal upon re-entry, a 1979 DOE-commissioned safety study found that "break-up of the reactor into non-respirable particles ... is preferable to uncontrolled intact re-entry or to high altitude vaporization." (26, 29) In other words, break-up into pepper-flake sized particles like those produced by Cosmos 954 is the best (as well as the most likely) form of reentry. This finding led one U.S. official to endorse such break-up as "an acceptable backup option" should high-orbit disposal fail. (26) However, certain assumptions of the 1979 study have since been called into question, and the whole dispersal issue today is officially under review. (20)
Although the American planners have obviously been concerned enough about safety to draft general criteria and institute a three-step, multi-agency review process that must be completed before each launch (31), there are a number of weaknesses in the U.S. regulatory system vis a vis NPS. First of all, there is no licensing by an independent authority like the Nuclear Regulatory Commission, the watchdog of America's commercial nuclear power industry. All the nuclear missions flown to date have been classed as research devices and have therefore been exempted from licensing under a provision of the Atomic Energy Act. (14) DOE, meanwhile, reserves the right to approve deviations from the published safety criteria. (31) And, perhaps most importantly, there is no provision for public participation in the safety review process.
Unlike commercial nuclear plants, which have a small probability of catastrophic failure, due to the presence of carefully engineered redundant safety systems, each orbiting nuclear reactor is virtually certain to undergo a major loss of containment upon its inevitable plunge to earth. (Unless future generations are to be saddled with the task of retrieving or re-boosting the worn out NPSs of today.) Even after several hundred or thousand years, certain radioactive substances (alpha-emitters) will remain on board in significant quantities, even though general radiation levels will substantially subside. The toxicity of these long-lived carcinogens is a contentious issue among medical experts, and it is possible that prevailing attitudes as to the safety even of high-orbit missions will someday have to be revised.
Meanwhile, the U.S. space reactor program forges ahead, spurred on by Star Wars dreams of electrically driven particle beam weapons, high-velocity anti-missile "rail guns", and radar powerful enough to track Russian submarines beneath the sea. Soviet RORSATs like Cosmos 954 also continue to circle above. (33)
Against this backdrop, there exists only a piteously weak international regulatory regime, consisting mainly of a procedure for notifying others when one's own NPS is about to fall. Despite recent official recognition by Canada and other delegations that "debris from re-entering satellites could become the chief source of artificial radionuclides [i.e. atomic fallout] in the atmosphere in the next century," (34) eight years after Cosmos 954, the world body is still "just beginning to deal with legal principles" and "trying to pin down general ideas," according to a Canadian representative to UNCOPUOS. (35)
In order to reach some kind of agreement, Canada has even expressed official willingness to compromise on its principle of opposition to low-orbit NPS and "consider a specific exception for national security reasons," on condition that "states be obliged to announce in advance that they would be using reactors in low-earth orbit." (36) Washington and Moscow have refused to agree.
Thus, the U.N. remains deadlocked. A treaty, even by the most optimistic accounts, is still some five years down the road. The major opportunity afforded by Cosmos 954 for a historic breakthrough in the protection of the outer space environment has all but slipped away. Meanwhile, both superpowers are jealously guarding the right to keep silent about number and nature of nuclear powered satellites that may one day circle above.
The Animated Software Company
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The Animated Software Company
First placed online January 2nd, 1997.
Last modified March 27th, 1997.
Webwiz: Russell D. Hoffman
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