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Mars 96 Failure Fuels Cassini Protest
by Dr. Robert M. Bowman, Lt. Col., USAF, retired

In June 1996, we published a report on Cassini and the risks associated with the launch and operation of a spacecraft containing Plutonium pellets. We concluded that the potential benefits of Cassini outweighed the risk, that the dangers had been grossly exxagerated by opponents, and that it would be a mistake for the peace movement to take a position against the launch.

In spite of that, a handful of peace groups, led by Bruce Gagnon of the Florida Coalition for Peace and Justice and Karl Grossman, have continued their vocal opposition.

The recent failure of the Russian Mars 96 probe and its reentry and impact on the earth have raised new fears and reignited interest in the risks associated with Cassini. Indeed, it is one of the factors leading NASA to reconsider their lauch accident scenarios. By the time you read this, NASA will have announced that they are conducting a Supplemental Environmental Impact Study and will issue a draft Supplemental Environmental Impact Statement (EIS) by mid-April. The public will, as usual, be invited to participate by asking questions and submitting comments to be published with the final EIS. NASA hopes to publish the final document by August (lots of luck; that’s a very ambitious schedule.).

My guess is that the odds of some accident scenarios coming about will go up, perhaps significantly, and entirely new scenarios may show up. This will greatly excite the opponents of Cassini and embarrass NASA. But I predict that in the end, the bottom line will be pretty much the same. NASA will claim that although odds of an accident are higher than previously thought, chances of human exposure to Plutonium are still very small. Opponents will say that the risk is much higher than NASA will admit to, and that any risk that endangers so many people is unacceptable. NASA and the government will be unmoved. Opponents will demonstrate. The launch will happen. We will all survive, and things will go back to normal — until next time. It all depends on whom you believe.

Having been on the inside for so many years, I certainly don’t believe the government, just because they say something. My first-hand experience with government lying to the people (and even to itself) is substantial. My inclination is to believe the critics. But this happens to be an area where I have some expertise, and where I have devoted countless hours to research. So I don’t have to take the word of either side. I can come to my own conclusions. For those of you who may be interested in those conclusions, here they are. I will begin by discussing the Mars 96 failure (something, by the way, that the government has already been caught lying about). Then we will proceed to an updated version of my Jun 1996 article "Rethinking Cassini & RTGs" (S&SN, Vol XIII, No 2). By the way, for those of you who haven’t read my previous articles, RTG stands for Radioisotope Thermal Generator. More on this later, but now lets look at Mars 96.

The Mars 96 Failure

On November 16, 1996, the Russian Mars 96 probe failed to achieve its trajectory toward Mars, and reentered the earth’s atmosphere. Apparently an upper stage failed to ignite.

President Clinton, at the suggestion of Space Command, which had been tracking Mars 96, warned the government of Australia that it looked like the spacecraft would land there. Australian officials went on full alert. After it came down, we were told that it had missed Australia and had fallen harmlessly in the middle of the Pacific Ocean. Two weeks went by. Then it was revealed that the spacecraft had come down in South America, either in Chile or Bolivia, along with its 0.44 pounds of Plutonium.

This chain of events raised a series of questions, especially among the skeptics and opponents of Cassini. Why did the failure happen? Why did we get the predicted impact area so very wrong? How could the public have been misled for two weeks about where it actually came down? Was it more government lies, or just gross incompetence? What happened to the Plutonium? Did it burn up and get spread into the atmosphere to affect large numbers of people? Did it come down in one piece where some unfortunate soul could come in contact with it? What is going on here?

The leading opponents of Cassini didn’t wait for answers. They put out a funding appeal: "We must protect our children and this fragile planet from more nuclear accidents like the Russian Mars space probe." But for those of you who want to know what happened, this is the story, as best I can piece it together:

When the Russian upper stage failed, and it was clear that Mars 96 would be coming back down, Space Command (deep inside Cheyenne Mountain, west of Colorado Springs) went into action. Predicting reentry points is, after all, part of their primary mission. But this was not a ballistic missile (whose aerodynamics and trajectory are pretty well known). This was a planetary probe. No two are alike. Space Command didn’t have very good information on this one from the Russians. To predict an impact point, you have to know the object’s weight, its shape, and the distribution of its weight, so you can calculate whether it will tumble or roll during reentry. Aerodynamic drag depends not only on shape, but on orientation as well. If the thing’s tumbling, aerodynamic forces are continually changing. So such predictions are never easy. This one was further complicated by two factors: the lack of accurate information from the Russians, and the lack of tracking coverage in the southern hemisphere. Remember, Space Command was originally created to detect and track Soviet ballistic missiles and aircraft coming over the North Pole. Eventually, they developed the capability to track threats no matter where they came from. But their coverage is still not as good over the southern hemisphere as it is over the north. These factors led to the initial mistaken prediction of an impact in Australia. What should have been relief that their prediction didn’t come to pass turned to intense embarrassment at just how wrong they had been. What’s worse, they had involved the President in the embarrassment. They had him warning the Aussies, when he should have been on the horn to governments in South America.

We can’t be sure if Space Command knew immediately about the Chile/Bolivia impact. But we do know that they knew for at least a week before admitting the magnitude of their error. Why did they leave the American people for a whole week thinking the debris had impacted safely in the ocean, when they knew better? Maybe they thought no one would notice. If so, they were wrong, for a whole bunch of people in Chile watched Mars 96 disintegrate as it streaked overhead. My guess is that Space Command dragged their feet out of embarrassment. Who in the government knew what when, we will probably never find out. As it turns out, the delay probably didn’t make much difference. The plutonium is still missing, and no one seems to be looking very hard for it. But it could have made a difference. Delay in fessing up could have meant injury to some unsuspecting Bolivian peasant coming across the debris. So was it government lying or just gross incompetence. My guess it was a bit of both. And it was wrong.

The next troubling question is about why we still haven’t found and recovered the Plutonium. I must warn you. The answer is even more troubling than the question. The Department of Energy is the agency with the technology, the knowhow, and the experts to locate a piece of Plutonium weighing less than half a pound. It would be a difficult and expensive search, particularly if it’s in forest. But if anyone can do it, they can. But it’s not our Plutonium. It’s not in our country. This is an international problem. It’s the State Department’s call. When DoE went to State with the estimated bill for the retrieval operation, State choked, then refused to pay. So the Department of Energy people are sitting home doing nothing, waiting for someone to authorize their efforts and pay for them.

Now to the question of what happened to the Plutonium. I haven’t actually seen a Russian RTG. But I have talked to those who have. They aren’t as high-tech as ours, but are designed to survive the same reentry environment and impact scenarios as ours are. The Russians achieve this by brute force, surrounding the Plutonium with metal cladding and then lots and lots of graphite. Russian RTGs wind up much heavier than ours to do the same jub. But that’s been the Russian approach to space all along. Have big powerful boosters and don’t skimp on the weight of what you put on them. The Russians have tested their RTGs against our standards, because they hope to qualify theirs to fly on our spacecraft. Our engineers and scientists haven’t been involved in the testing, so can’t vouch for the results. But their gut feel is that the Russian RTGs and their Plutonium probably did not burn up, but survived reentry and impacted intact. Whether they broke open at impact, we just don’t know. Chances are they did not. If we are correct about that, then it is not accurate to call this a "nuclear accident," because there is no human exposure, and no one hurt.

But the whole thing does raise valid issues to be considered carefully before we launch our own RTGs aboard Cassini. NASA is doing just that.

I would now like to point out some differences between Mars 96 and Cassini that are important in assessing how this incident should affect our thinking about the Cassini launch.

Differences Between Cassini and Mars 96

Could a failure similar to Mars 96 happen with Cassini? The answer to that is easy. "Yes." Is it likely? No. Both NASA and U.S. industry will point out that our launch vehicles are more reliable than those of Russia. The Centaur upper stage which will do the job the failed Russian stage tried to do is a tried and true workhorse. Of course a failure could happen. That’s why NASA has given Cassini the independent capability to boost itself into a high orbit, where it could survive for thousands of years without reentering. The Mars 96 didn’t have that capability. But what about a double failure? Could the Centaur fail and then the Cassini fail to get free of it or suffer a failure of its own propulsion? Sure. Double failures do occur. Much more often than reliability engineers like to think. Yet to be fair, the chances are indeed slim.

But if such a double failure did occur, then what? Would the Plutonium RTGs in Cassini survive reentry without burning up? The tech people give an unqualified yes. "We think the Russian RTGs could survive. But we know ours can."

This is important, because one obvious difference between Cassini and Mars 96 is that Cassini will be carrying about 166 times as much Plutonium. If you worry about Mars 96 having burned up and spread Plutonium vapor around, then you have a right to be petrified about Cassini.

And what about Space Command? Would it perform as pitifully during a Cassini reentry as it did for Mars 96? Not likely! For one thing, JPL (NASA’s Jet Propulsion Laboratory, which run’s the Cassini program) has given Space Command detailed and accurate information on Cassini which will help them with impact prediction during such an event. Secondly, Cassini will not be flying through any blind spots in Space Command’s coverage. So impact prediction should be much better.

Finally, should such an event occur, it will be our Plutonium, and the State Department will not be able to opt out of paying for the retrieval and cleanup.

In the final analysis, the Mars 96 failure means very little with respect to the risks of Cassini, because the chances of Plutonium release due to launch or staging failure are much smaller than the more important risks associated with accidental reentry during Earth flyby. And my guess is that new information will increase the minimal risks of the launch phase, but actually decrease the dangers of the flyby. We won’t know for sure until the analyses are complete and the Supplemental EIS comes out. (Of course, critics will claim that we won’t really know then either. To some extent, they’re right.)

Having dealt with this very recent information, let us now proceed to a detailed update of the risks of Cassini and my advice to those in the peace and justice movement. For comparison, I have used Galileo, which is at this moment sending us back spectacular pictures of Jupiter and its moons.

GALILEO & CASSINI COMMON FACTORS

RTGs: Both missions use plutonium in Radioisotope Thermal Generators (RTGs) as a source of electrical power. They are not reactors. Nothing is reacting. The plutonium is merely decaying according to fixed physical laws, much as the radium in an old watch dial or the radon under your house. There is no chain reaction. There is no critical mass. There is no possibility of explosion. The plutonium, as it decays, releases heat, which is turned into electricity to power the spacecraft on its 11-year journey.

Plutonium: Plutonium is nasty stuff. Not only can it be made into nuclear weapons, but it is often called the most toxic substance on earth. It is often said that one pound, if evenly spread, could cause lung cancer in every person on earth. While this statement is theoretically true, it is enormously misleading. It is quite difficult to get plutonium into a person's lungs (which is fortunate, because the nuclear testing of the 50s and 60s put about 14,000 pounds of plutonium into the atmosphere!). The radiation from the decay of plutonium 238 is made up of alpha particles (helium atoms without their electrons). This form of radiation is in general less hazardous than that made up of gamma rays (pure energy) or neutrons, both of which penetrate the body far easier than alpha particles. Of these three types of radiation, alpha particles are the only ones with an electric charge. This positive charge makes it almost impossible for an alpha particle to penetrate an ordinary piece of paper or an article of clothing or even the skin. What's more, the particular chemical form of plutonium used in RTGs (plutonium 238 dioxide) is highly insoluble in water and thus has great difficulty getting into the food chain. It also means that if swallowed, it generally passes through the body without being absorbed and without having time to do any damage. The primary way plutonium dioxide can be dangerous is if it is pulverized into tiny particles and breathed into the lungs. Since it can lodge there for years, the accumulated radiation can do great damage over a long period of time. It is this potential for long-term radiation damage which gives plutonium its ability to cause lung, bone, or liver cancer. But the range of sizes which pose this danger is fairly small. If the particles are too big, they don’t get inhaled. If they are too small, they get inhaled, but get exhaled right out again. Big hunks are not very dangerous at all. One reason we are all so concerned about the tons of plutonium lying around as a result of the dismantling of Cold War nuclear weapons is that it is too easily stolen, because it can be safely handled with an ordinary pair of gloves.

Release of Plutonium: For years, various groups have been exploring ways of getting rid of the plutonium left over from the Cold War. One suggestion was to put it on top of rockets and fire it off to the sun. The problem we found with that is that to make it safe in case of a launch failure, you have to encase the plutonium in much larger heavier containers capable of withstanding the forces of an explosion or crash landing without releasing plutonium into the environment. To do this with tons of plutonium is clearly impractical. Yet it's not impractical for a few pounds, and that is exactly what is done with an RTG. Each little ball of plutonium is encased in a much larger, almost indestructible sphere. To rupture one of these fuel pellets would require an impact with a sharp, hard object (like an ax) striking with incredible force (much more than was generated in the Challenger explosion, for example). To say (as some have done) that "If there's an accident like Challenger you can kiss Florida goodbye" is the height of irresponsibility. If there had been RTGs aboard Challenger, there would have been no plutonium released at all, and no danger to anyone in Florida. Even in the extremely unlikely event that the pellets ruptured and plutonium was released, the number of people affected would be very small. Every successful Shuttle launch probably causes more cancer (through release of toxics from the Solid Rocket Boosters and through damage to the ozone layer) than would a failed launch involving release of plutonium from RTGs.

Earth flyby: To propel a spacecraft away from the Earth against the Earth's gravitational attraction takes considerable energy, and a good sized rocket. To shoot it to the outer planets, against the pull of the Sun's gravity, takes lots more energy, and would require a much bigger rocket than we have ever built. So missions to the outer planets take an indirect route, flying by nearby planets to pick up additional energy in a "slingshot" maneuver called "gravity assist." Both Galileo and Cassini use both Venus and the Earth itself for gravity assist. The Galileo mission involved two flybys of the Earth. Cassini will use just one. Critics of these missions complain of the danger of these flybys, fearing that an error could cause the spacecraft to strike the Earth, releasing its plutonium and causing a worldwide catastrophe. This fear is again based on a lack of understanding. It is possible for a flyby to go wrong and result in the spacecraft striking the Earth. But this would require multiple failures. The spacecraft is never pointed at the Earth. If at any time it becomes impossible to correct the spacecraft's course, it would miss the Earth by thousands of miles. It is only as it approaches Earth that course corrections are fed to it to reduce its miss distance, bringing it close enough to gather the necessary gravity assist. Independent study groups for Galileo concluded that the chance of impacting Earth or its atmosphere in a flyby is one in two million. The next question is, "If it does occur, how big is the problem?" There are three possibilities: (1) the pellets survive to the surface and remain intact, in which case no plutonium is released; (2) the pellets tumble as they fall, reaching the surface intact, but strike hard rock and burst open upon impact. In this case a very few people would be exposed to cumulative doses of up to 269 REM (It is generally accepted that 5000 person-REMs yields one cancer fatality.); (3) the pellets do not tumble, so that reentry heating is concentrated and results in the pellets burning up before striking the ground. If this happens, the plutonium is distributed over a much larger area and affects many more people. Up to 2000 people could ingest plutonium particles, with a maximum individual dose being .002 REM. Experts disagree about whether it is possible to get cancer from such a low dose. Assuming it is, a few of the 2000 people might develop cancer in the subsequent 50 years. In any event, the worst possible result of such an unlikely impact would be small. The risk is not zero, but is insignificant compared to the risks we accept every day from radars, power lines, ozone depletion, or riding in a car. For those of us living in Florida, the risk is insignificant compared to that of being struck by lightning.

Having looked at the common factors in the two missions, let us now take a look at the ways in which Cassini differs from Galileo.

IMPORTANT DIFFERENCES WITH CASSINI

The Cassini spacecraft is scheduled to be launched in October 1997 atop a Titan IV rocket with a Centaur upper stage. It will swing by Venus twice, Earth once, and Jupiter once, gaining energy from gravity assist each time. It is scheduled to arrive at Saturn in June 2004. It will deploy the Huygens probe (supplied by the European Space Agency), which will descend to the surface of Titan, an Earth-like moon with a nitrogen atmosphere resembling that of early Earth. Cassini will then spend four years orbiting Saturn, examining its rings, and performing flybys of its many moons.

This mission differs from Galileo in several important ways: (1) its destination (Saturn) is twice as far from the Sun as Jupiter, Galileo's destination; (2) the lifetime of the spacecraft has to be longer, since it takes about four years longer to reach Saturn; (3) the launch vehicle is an unmanned Titan IV/Centaur instead of the Shuttle with an IUS upper stage; (4) the mission requires only one Earth flyby instead of two; (5) it carries three RTGs instead of two; and (6) the scientific knowledge achievable at Titan could have more direct application to the understanding of Earth's atmosphere.

Distance: Solar intensity falls off with the square of the distance from the sun; so since Saturn is twice as far as Jupiter, the solar intensity is one-fourth what it is at Jupiter. My analysis of the Galileo mission concluded that it was totally impractical to rely on solar cells (with or without concentrators) for the electrical power for the mission. The required solar array would be perhaps 100 times as large as would be required in Earth orbit. The size, weight, and reliability problems would be totally unacceptable. This made RTGs essential. Since the arrays at Saturn would have to be four times as large for the same power, just to compensate for the low solar intensity, the conclusion for Cassini is even stronger. For the foreseeable future, there will be no acceptable alternative to plutonium RTGs for such missions.

Lifetime: Because Saturn is so far away, it will take much longer to get there than to go to Jupiter. Cassini will take seven years to get to Saturn, and another four years to accomplish its nominal mission. This means that everything (including the power source) must last for at least eleven years. Such a lifetime is easily achieved with RTGs. But solar arrays degrade with time, putting out less and less power. So even if they could be made to last eleven years, they would have to be drastically oversized to compensate for this degradation. And, as we have seen above, they would be impossibly large, even before such oversizing. In addition, solar systems have many more catastrophic failure modes than RTGs, making it extremely difficult to count on them for such a lengthy mission. With the current state of technology, either we use RTGs to go to Saturn, or we don't go at all.

Launch Vehicle: In my 1989 article on Galileo, I pointed out that there was one failure scenario unique to the Shuttle that could result in plutonium release: "If a Solid Rocket Booster (SRB) exploded, it could send fragments of its metal case flying outward at high speed, something like the shrapnel from a hand grenade. If one of those pieces were to penetrate the wall of the cargo bay and impact the RTG at the right angle (it would have to be within about 15 degrees of edge-on), it might slice a fuel pellet open like a knife, resulting in some plutonium release. On the shuttle, the satellite is located right between the two SRBs and is therefore likely to be hit by shrapnel if one of them explodes. On a Titan IV, the satellite would be in a shroud on top of the 'stack,' several stories above the solid rocket boosters. My judgment is that there's not enough risk to consider delaying Galileo in order to switch launch vehicles (the necessary redesign would take about three years). But in the future, planetary probes (which all have RTGs) should be launched on expendable rockets."

NASA has now adopted this position, and Cassini and all future planetary probes will be launched atop expendable rockets, eliminating the most likely plutonium release scenario. This change should be comforting to those who felt uneasy about Galileo launching in the Shuttle cargo bay.

Number of flybys and RTGs: These two changes tend to cancel each other out. When combined with the change in launch vehicle discussed above, the Cassini mission seems to be significantly safer than Galileo (whose risk we judged to be minute and acceptable).

Benefits: As we said in 1989, "Only by understanding what has happened to our neighboring planets in the solar system can we figure out what is happening to our own atmosphere, oceans, and life support systems." This is even more true of Cassini, whose Huygens probe will explore a very Earth-like body -- Titan.

ARGUMENTS OF THE CRITICS

Those who fought Galileo and Ulysses and are now fighting Cassini seem to have four main arguments: (1) the government is lying to us again; the danger to the public is much higher than NASA admits; (2) RTGs are not required for the mission; solar can do the job; (3) it's just an excuse to keep the plutonium production lines open so they can build more weapons; and (4) flying plutonium in RTGs on planetary missions is meant to soften the public up to accept nuclear reactors in Earth orbit and all manner of space weapons powered by them. Let's take a look at these arguments:

More government lies: I wouldn't be surprised. After all, everything we've done since 1981 has been devoted to exposing government lies. But to expose a lie, you have to catch them at it. You have to discover the truth that they are trying to avoid, destroy, or cover up. You expose lies with the truth, not falsehoods of your own. In my investigation of Galileo, I found places where the government had shaded the truth or exaggerated to make its case. Some of the risk calculations were a little suspect. But in general, I could not disagree with their conclusions. The same is true for Cassini. In fact, it appears that NASA has eliminated some of the over-optimism from their failure analysis. The literature of the critics, on the other hand, is loaded with fabrications and distortions. Talking about the Galileo launch, they said, "It only takes one Challenger or one Chernobyl accident in space to destroy life on our planet." There is not a shred of truth in that statement. Such blatant propaganda is reminiscent of the fundraising scare tactics of the radical right. It belongs in the Enquirer, not a publication of the peace and justice movement. We will continue to try to protect the American people from lies -- whether from the government or another source. We will not invent or promote our own lies in support of any ideology. To do so would be to be no better than Ollie North.

Solar Can Do It: This criticism is based largely on the over-enthusiastic salesmanship of solar researchers. During the Galileo debate, a pair of JPL researchers issued a report in which they claimed that a solar concentrator which they had dreamed up could (in theory) power a spacecraft on a mission like Galileo. Having been in the business for many years, on both the government and industry side, I know very well how such reports originate. What motivation would anyone have for writing a paper telling what can’t be done? From a systems engineering perspective, the proposal was totally unrealistic. I don’t believe anyone but Galileo critics took it seriously.

Now, the critics are saying that the European Space Agency (ESA) claims they can do Cassini with solar. Of course, ESA made no such claim. What really happened was that an ESA scientist announced that she had developed a new type of solar cell in the laboratory, one with about 25% more efficiency. A reporter asked her if her new cell could work at Saturn. She said "yes." Cassini was never even mentioned. She was misquoted and the whole thing was blown out of proportion. Sure her solar cell could operate around Saturn. So could our present cells (if you could get enough of them there). But from a laboratory cell to mass-produced cells to a solar array takes many years. Then many more years of testing. Solar cells we developed twenty years ago are still not ready for operational use! And even if these new cells could be magically produced into a working array, it would be much too big for any existing launch vehicle. Then, if you could somehow get it into space, how would you unfurl this huge structure? We couldn’t even get a simple communications antenna on Galileo to open up. People have to understand that there’s a big difference between what a scientist does in the laboratory and what a systems engineer can actually do on a real spacecraft subjected to the intense heat, cold, shock, vibration, and radiation environment of space.

Plutonium Production: Even in 1989, we had more plutonium than we needed. It was not believable even then that RTGs were an excuse to keep plutonium production going. But now that the world is awash in tons of excess plutonium that we don't know how to get rid of, it is downright ludicrous. I hope no one continues to use this excuse to oppose Cassini.

RTGs now, Reactors later: The critics argue that if the government gets us to accept RTGs now, then it will be able to put reactors in Earth orbit when they're ready, and the public will accept it. "Nukes in space is nukes in space." If there is a more self-defeating argument than this, I don't know what it is. RTGs have been used safely on planetary probes for decades, including missions like Voyager enjoying great public support. The few nuclear reactors ever put into space, on the other hand, had a dismal and failure-ridden history. One spread radioactive debris across Canada. Those of us who oppose space weapons and the dangerous reactors that power them have a clear course: we must maintain the distinctions, not blur them.

And who is it that is getting the public used to nuclear materials in space? It is the critics of Galileo, Ulysses, and Cassini. The public at large would never have even given it a thought, except for the critics. How many people even knew that the Voyagers were powered by plutonium? How many cared? The critics are getting the public used to hearing all sorts of dire scare talk about "nukes in space" and nothing gets changed and nothing bad happens. Having cried "wolf" so often, do these critics think the public will pay any attention if we have to protest something really dangerous some day? If some future government tries to put a "Star Wars" nuclear reactor in orbit around the earth, and we object, what will people think? "Oh, it’s just those anti-nuke loonies again. They’ve been doing these protests for years. Nobody pays any attention." We can’t let that happen. We must maintain our credibility for when we need it. If the diehard critics continue their foolhardy course, the rest of us must disavow them. Most of the grass-roots demonstrators are really good-hearted souls. But they have been led astray by a few leaders with their own agenda. Opposing Galileo and Cassini is a good short-term organizing strategy. It brings in new members and new money. But in the long run it can destroy our movement.

The people at the Jet Propulsion Laboratory (JPL) who run the planetary programs for NASA don’t have the slightest interest in being stalking horses for the pentagon or the nuclear industry. They are just quietly trying to do their job. By trying to tie them into some grand conspiracy to nuclearize earth orbit, the handful of critics in the peace movement are destroying their own credibility and alienating natural allies.

CONCLUSIONS

*RTGs yes; Reactors NO! They are very different things. RTGs safely provide small amounts of electrical power for peaceful space missions which can be conducted no other way. Reactors are orders of magnitude more dangerous, and are totally unnecessary for any legitimate purpose.

*Plutonium in RTGs to the outer planets, yes; Radioactive materials of any kind in Earth orbit, NO! RTGs, safe as they are, should not be placed in Earth orbit, because of the possibility of accidental reentry. Besides, they are not needed in Earth orbit, because we have plenty of solar intensity here. Solar cells can do the job here, so they should.

*Peaceful space missions, yes; space weapons NO! Space weapons are in violation of international law and our treaty obligations. Besides, military analysis has shown conclusively that space weapons are counterproductive to our security and increase the likelihood of war.

The critics of Galileo and Cassini, by denying the existence of these distinctions, play into the hands of the Star Warriors who want nuclear-powered battle stations circling our planet to maintain the status quo of the global power elite. Unless there are some big surprises in the new Supplemental Environmental Impact Statement, we urge all progressives to avoid getting embroiled in a wrongheaded battle against Cassini.

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