Opening Remarks, Answers to Questions, and Closing Remarks

Opening remarks of Ross McCluney, Ph.D.
Rollins College, Winter Park, Florida 3 October 1997

NASA said solar wouldnít work on the Galileo mission to Jupiter, launched on 18 October in 1989.

Two weeks after the Galileo launch, a long-sought Freedom of Information Act request, delayed for over two years, was filled, releasing an internal JPL report from 1981 saying that solar could have substituted for nuclear power for the Galileo probe. This report was finally released only after the launch was a done deal.

Now they say that solar wonít work on Cassini.

Why should we believe them this time? Is this any different from the Galileo case?

To be sure, using solar is more difficult. Saturnís further from the sun. The available sunlight is only about one-percent as strong as it is at the Earthís distance from the sun substantially less than itís strength at Jupiter. A much bigger solar collection area is required, about as big as two tennis courts. The big panels might tend to get in the way of the observing instruments. Keeping them pointed toward the sun while the spacecraft flys around the vicinity of Saturn could be a problem. If they just use the same kind of solar cells used on near-Earth missions, the sheer mass of them is so much greater that NASA claims the biggest rocket they have canít lift the Cassini spacecraft, with all its experiments and sub-experiments, and the solar arrays too, to Saturn.

These seem like daunting problems. They say JPL has explored all the options and canít find a way to make solar work.

Whatís really going on here? Thatís difficult to say, because of the secrecy NASA places around its nominally civilian space probes whenever thereís any significant nuclear material on board. We can make a few educated guesses, however. First of all, let me sympathisize with the scientists responsible for the experiments on Cassini.

I know how important the Cassini mission is to them. Theyíve put a lot of their time and professional reputations on the line for this mission, despite the risks that the mission might not be completed. Although Iím sympathetic with these mission scientists, at least I know they are aware of the fact that rockets fail, guidance systems fail, and sometimes interplanetary probes just stop talking to them, as happened recently with the $800 M Mars Observer. So my sympathy for them is muted, since they know well the overall risk that they may get no scientific data at all from Cassini, regardless of the probeís source of power. In a nuclear powered mission, failure means more than just loss of data. Something far more important can be lost.

Now letís look at NASA and the U.S. government interest. The Cassini spacecraft is huge, and NASA proudly boasts about its size. It is very expensive. Many nations of the world are collaborating on the Cassini mission. The entire astronomical community has been waiting a long time with high expectations for this much science on one launch. Iím very excited about it as well. I canít wait to see the close-up results from Saturn, shown to the world on JPL web sites, as they are doing now for the marvelous Mars Pathfinder mission. So there is an enormous amount of money, and sweat equity, invested in the Cassini mission. Of course, for purely political reasons, the government and NASA will be inclined to do just about anything to keep it from being stopped.

One thing that really worries me is that if the President merely calls a halt to the launch, instead of making a statement on how cooler heads can prevail and how we can learn political lessons from the demise of nuclear powered space missions, heíll be afraid that cancellation would appear to be a repudiation of NASA planners, who have been pushing this thing for years, allowing it to get bigger and bigger, and more complex, and locking in the nuclear power option.

Returning to the solar issue, basically NASA says that to fill the 745 Watt power demand near Saturn with solar cells of the current efficiency gives the problems mentioned previously, and these are sufficient to declare that solar canít be used for the current Cassini design.

Letís look at some alternatives NASA may not have considered, or may just have swept under the rug because they didnít want to stop the mission, delay it, or split it into smaller missions.

Here are my main arguments, the things NASA can, or could, do to eliminate the RTGís from this and future probes to Saturn.

  1. Use new high-efficiency solar cells, described by many authors, and announced by several different companies, which boast efficiencies as great as 25% under deep space conditions. This is almost a factor-of-two increase over the efficiencies of older solar cells, and could alone reduce the area and mass requirements for solar power for future space probes by that same factor. Just using these new solar cells alone could reduce the size of the array needed to power the current Cassini design by somewhere between 30% and 60%.

    Of course, these new cells have not yet been tested and proven to work reliably in the space environment near Saturn, especially in the cold so far from the sun. So it may take a few years to get them in a durable and tested form for use in space, but what's the rush? Saturn will still be there when an Earth-safe probe is designed.

  2. Use new, strong, lightweight solar concentrators. Thereís a new class of what are called "non-imaging optical systems" that can deliver high concentration ratios. NASA could develop new light-weight concentrator systems using the new optics so that fewer solar cells are needed, with a further reduction of weight. An added advantage is that the concentration increases solar flux levels on the cells and thereby increases their operating temperatures and hence efficiency. Of course this means a major increase in NASAís tiny budget for solar options. But RTGís are very, very expensive power options, one of the main reasons they donít like using them for near-sun space probes.

    It will take a little time to explore the use of solar concentrators in space, but what's the rush?

  3. Use new low-power electronics which need far less power to perform the electronic and computer portions of the mission. The July 1997 issue of Military and Aerospace Electronics ran an article titled "Low power experiment set for space" which describes these new developments.

    If the power needs of the spacecraft are cut in half by using the new electronic systems, so is the size of the solar collection system to meet these requirements. Of course NASA says that these low-power electronic systems are still in the research stage and some time will be needed to assure their readiness for space, but what's the rush?

  4. Split the mission into more smaller, better, faster, cheaper ones. Cassini is a relic of the Cold War era of large, long-drawn-out, expensive space missions, a direct violation of NASA Administrator Goldin's much touted new dictum for "faster, better, cheaper" missions. Yes, it would probably take a some time to split the Cassini probe into several smaller ones, basically redesigning much of the vehicle that delivers the payloads to their destinations, but what's the rush?

So there are my four options. Any two of them could make solar feasible for Cassini. Putting all four of them together makes it a sure thing.

Lest you think thereís anything particularly new in this, I came across a paper by Paul Stella of JPL, delivered at a meeting on space power systems in 1985. His opening paragraph anticipated the new NASA dictum for "faster, better, cheaper" missions.

"Future U.S. interplanetary missions will be less complex and costly than past missions such as Voyager and the soon to be launched Galileo. This will be required in order to achieve a balanced exploration program that can be sustained within the context of a limited budget. Radioisotope Thermoelectric Generators (RTGs) have served as the power source for missions beyond the orbit of Mars. Recent government costing practices have indicated that the cost to the user of these power sources will significantly increase. Solar arrays can provide a low cost alternative for a number of missions."

He described the recommendations of a 1980 high level NASA Solar System Exploration Committee and said, "Of major importance, the program established a critical level of activity consistent with a realistic sustainable budget, ... to provide for stability...the approach specified highly focused, less complex missions that could rely heavily on existing technology and hardware inheritance to reduce costs. Whereas the cost of some early missions ... had exceeded two billion dollars total, the new plan would be based on a total annual funding level of ~$300 M (FY Ď84)." ... " A critical item in any of these missions is the power source."....

He mentioned some probes where RTGís seemed to be best, and then went on to say: "However, within the past few years the cost of RTGs has come under examination. Historically, the cost of the fuel for an RTG power source has been "subsidized" by DOE, resulting in a relatively low RTG cost to NASA." He mentioned that this was under review and said that if NASA were required to assume these costs, the cost of them per mission would be prohibitive within the context of a constrained budget. "For this reason a number of missions which normally might be RTG powered are potentially open to photovoltaic power." He then goes on to discuss a variety of ways that solar cells can be used for outer planet exploration, including the use of concentrators and novel array configurations to reduce view blockage of the sensors on the spacecraft. There was no mention in this Stella report of the safety hazards of massive RTGís, because Iím sure he was focusing only on the engineering, not on the safety and political aspects which are handled elsewhere in NASA.

Of course there are difficulties when you have a big solar collector hanging onto your planet probe. You have to keep it pointed toward the sun, even when the spacecraft has to twist around to keep pointed toward the target, especially important during approaches, where the spacecraft moves rapidly toward or by the target being observed. However, you also have to point the communications antenna toward the Earth, routinely done at high accuracy now, better than 1/10 of a degree. At Saturn distances, the Earth is quite close to the sun, so the pointing of a solar array and an antenna should not be incompatible.

The main point I have to make here is that I donít see a lot of innovative options being explored, such as incorporating some solar concentration into the same structure used for the communication antenna, or the use of very lightweight inflatable concentration mirrors, which can be made rigid chemically after inflation, [ref., Sheila Bailey, NASA/LeRC] to reduce the consequences of micrometeorite impact. An advantage of concentrating collectors is that light pipes could be used to carry the sunlight to the solar cells, which could be put inside special housings to protect them from damage due to the space environment.

The nuclear powered Cassini spacecraft is a relic of Cold War mentality, when bigger, costlier, more lethal held us captive. Letís do away with it now, and free ourselves, while we still have the chance. Watch 60 Minutes on CBS Sunday night and then call the President at 202-456-1414.


Q & A Rollins College 3 October 1997

  1. NASA claims of accident and disaster probabilities.

    A lot has been said about one chance in a million for this accident and one in several thousand for that one. This does not mean it will take a million or several thousand launches for the accident to happen. It could happen on the first, the tenth or the thousandth.

    The problem is with the thinking behind these numbers in the first place.

    Even if they didnít "cook the numbers," as Dr. Kaku has claimed, whatís the practical difference between 1 in 1000 or 1 in 10,000? It doesnít really matter when the consequences of a worst case scenario are so terribly bad.

    If there is even an outside chance of badly contaminating a major portion of Brevard County, where I live, or of putting invisible, relatively undetectable plutonium dust in the lungs of Central Florida citizens, leading to cancer a few years hence, untraceable to the launch accident, then why do it at all? This is the real question you should ask when you hear the big numbers.

  2. "Trust us."

    If I, your friend, ask you to stand on the table, facing away from me, and fall backwards into my arms, you may be reluctant. But Iím your friend and I say "trust me." Suppose you go ahead and take the fall, but I donít catch you. How long do you think it will be before you are willing to trust me again? How many times must this event be repeated, with a safety net, and I do catch you, before you will be willing to try again?

    Never accept a personís request for trust on face value. The best test of the trustworthiness of a person, or a government, is history. Letís look at the history of the U.S. government in building trust in large scale nuclear projects.

    We begin with the Manhattan project. Super secret. Physicists who should have known better exposed themselves and lots of army personnel and private citizens to nuclear radiation, both accidentally and on purpose, to see what the effects would be, never cautioning the innocents of the dangers involved. Some airborne troops were sent to parachute into fallout areas.

    Then comes the atmospheric nuclear bomb tests of the 50's. The National Cancer Institute reported in August that the fallout from these tests had probably caused 10,000 to 75,000 extra thyroid cancers, over wide areas in the U.S. We learn that the U.S. government was aware of these effects and yet persisted in continuing the tests until the consequences were too obvious and too politically difficult to hide. And then we had a global nuclear test ban treaty.

    Now we learn that our same government was repeatedly informing photographic film manufacturers about fallout from the tests so that they could prevent their newly made film from being fogged up by the radiation. Yet this same government agency not only did not tell the people of the United States about how this fallout could contaminate their bodies, but it reassured the public that there was no health threat from the tests.

    We were told in 1987 and 1988 that the Galileo mission to Jupiter could not contain solar cells. Then, after the probe was launched we find out that the government knew all along that they could have converted Galileo to solar power and taken the radioactive substances off of it.

    Now they tell us to trust them with Cassini. How many times have we fallen off the table and been hurt already? They ask us to do it again? They tell us not to worry about an accident with Cassini. Beverly Cook says it is almost impossible to produce significant radioactive contamination, either outside of KSC at launch or around the world on the flyby maneuver.

    Suppose, while you are standing on the table waiting to fall back into my arms, you hear me chuckling, or you hear my voice waver when I tell you to trust me, or you catch a glimpse of me in a mirror, and you get an inkling that I may be about to pull a fast one on you, do you still trust me?

    Now, suppose you read a story by Liz Tucci in Space News which quotes NASAís chief scientist as saying about Cassini, "We canít fail with that mission. It would be very, very damaging for the agency" and going on to say that NASA Administrator Dan Goldin would have cancelled Cassini if he thought he had a choice. He went on to say that "We would not start Cassini today. It is a hard program for [Goldin] morally to deal with, because it has got a number of enormous risk factors."

    What would that do to your trust of NASA and DOE in their claims for safety of the Cassini mission?

  3. The purity of science.

    We are told that science is the reason we have to go to Saturn and take a bunch of pictures and make some measurements. We are told that it is in the nature of humans to be curious and to seek knowledge, that the quest for knowledge is of value in and of itself.

    Well, perhaps that is true if the quest is both relatively benign and might produce significantly useful new knowledge. We ask what will this knowledge of Saturn be used for and are told by Spehalski that it is to help the environment, that better knowledge of Saturn might yield some small increase in knowledge of the Earthís history and dynamic evolution over geologic time. What irony. That we would risk major radioactive contamination of portions of the planet in order to learn a little about its history. How old is Saturn? At least 4.5 billion years. Will it be there several decades later when we most surely will have developed good solar power alternatives for its exploration? Of course. So donít give me all this stuff about the purity of science and the grand scientific quest when your science threatens my body.

  4. The military role.

    Let me read to you from the March 16 issue of Space News. "The NASA administrator and the commander of the Air Force Space Command agreed Feb. 28 to coordinate and consolidate Pentagon and space agency efforts ...." They "agreed to establish a Partnership Council that will meet twice a year to oversee consolidation of long-range planning, joint technology development programs, and consolidation of redundant assets." "Anticipated results of joint Air Force and NASA work include Ďstreamlining of operations costs, cross utilization of facilities capabilities, consolidation of redundant facilities, sharing of support services [read "contractors"], and leveraging of science and technology investments,í the agreement states."

    Now let me read to you from two Air Force documents describing plans for the military use and domination of space.

    From "Guardians of the High Frontier" we have this: "The Space Warfare Center at Falcon AFB Colo. [with its motto and arm patch that says ĎMasters of Spaceí] plays a major role in fully integrating space systems into the operational Air Force."

    "In the next several decades, the spirit of cooperation between Air Force, civil (NASA for example) and commercial space industries will become a way of life in the spacelift business."

    Speaking of "the space-based Air Force" it lists several operational goals for the Air Force, among them, "Globally dominant. Tomorrowís Air Force will likely dominate the air and space around the world using earth- and space-borne hypersonic transports to get equipment and people anywhere quickly. Selectively lethal. The Air Force may fight intense, decisive wars with great precision hitting hard while avoiding collateral damage in both Ďrealí space and in the computer Ďcyberspace.í"

    From the U.S. Space Commandís publication, "Vision for 2020," we have this:

    "Historically, military forces have evolved to protect national interests and investments Ė both military and economic. During the rise of sea commerce, nations built navies to protect and enhance their commercial interests. During the westward expansion of the continental United States, military outposts and the cavalry emerged to protect our wagon trains, settlements, and railroads." "The emergence of space power follows [this model.]" ".... During the early portion of the 21st century, space power will also evolve into a separate and equal medium of warfare. Likewise, space forces will emerge to protect military and commercial national interests and investment in the space medium due to their increasing importance."

    "The globalization of the world economy will also continue, with a widening between the Ďhavesí and Ďhave-nots.í Accelerating rates of technological development will be increasingly driven by the commercial sectorĖnot the military. Increased weapons lethality and precision will lead to new operational doctrine."

    "...space superiority is emerging as an essential element of battlefield success and future warfare."

    "Control of Space is the ability to assure access to space, freedom of operations within the space medium, and an ability to deny others the use of space, if required."

    What does the European Space Agency have to say about this?

    "Due to the importance of commerce and its effects on national security, the United States may evolve into the guardian of space commerce Ė similar to the historical example of navies protecting sea commerce."

    "USSPACECOM must assume a dynamic role in planning and executing joint military operations. Included in that planning should be the prospects for space defense and even space warfare. Development of ballistic missile defenses using space systems and planning for precision strike from space offers a counter to the worldwide proliferation of WMD [weapons of mass destruction]."

    Finally, it is well known that future military satellites will need huge quantities of electrical power, in short bursts, to power their secret high-power space-based weapons systems, including lasers, particle beams, and other hush-hush hardware. The power source of choice for this is nuclear. Itís just the only source they can think about for powering these advanced weapons systems. Every rocket with nuclear material on board it has to launch through our air space, either at Cape Canaveral or at Vandenberg Air Force Base in California. The latter is needed for polar orbits to give complete coverage of all points on Earth.

  5. Nuclear Trojan Horse

    Although we canít really prove the following conjecture, it seems that one of the reasons the government is so intent on launching Cassini, as well as a string of additional nuclear powered space missions, is to get the public accustomed to successful launches with ever-increasing quantities of nuclear material, until, one day, they think they will be able to launch an entire nuclear reactor with little public outcry, except for the few "nuts" who always protest those things. The general public will have been lulled into complacency by these relatively small nuclear missions, serving as Trojan Horses for the larger missions to come. The problem with this kind of thinking, if indeed anyone in a policy position is thinking this way, is that sooner or later one of those things is going to blow up or vaporize or some other way release nuclear materials in a damaging way, and the whole space venture, not to mention life as we know it, could be severely threatened in consequence.

  6. Who Calls the Shots?

    NASA says that Cassini and other future planetary explorations with RTGs on board are for scientific purposes, leading us to believe that it must be the scientists who call the shots in the agency, or at least that it is the scientific goals of the missions which are tantamount to the justifications NASA offers to the Congress and the American people in support of its budgets for the missions. We see NASA more and more influenced by its contractors, and a number of large multinational aerospace corporations, or aerospace divisions of even bigger corporations. The power of these corporations to set NASAís agenda is becoming greater and more obvious. The enterprise of space is now so large, and planned to be so large, that the scientists used to justify the missions are starting to become little more than pawns in the bigger game of corporate greed for the highly profitable military/nuclear/industrial complex.

    Just listen to this quote from Florida Today, last July. "There is no questionóthere are profits to be mined from high-tech platforms parked outside the Earthís atmosphere." Speaking of the new International Space Station, the article says "Many think the $40 billion space station will be the centerpiece of whatever steps are to be taken. Once assembly is complete and government science missions exhausted, advocates would like to see private tenants move in. In fact, the Commercial Space Act would make it law that the stationís priority is the Ďeconomic development of Earth orbital space.í"

    Exhaustion of the governmentís science missions? Could the real purpose of all these so-called scientific missions be any clearer? Who can doubt who really calls the shots at NASA? The agency is in danger of becoming little more than a conduit for an incredible new government welfare program for large multinational corporations.

  7. Whatís really going on here?

    Thatís difficult to say, because of the secrecy NASA places around its nominally civilian space probes whenever thereís any significant nuclear material on board. We can make a few educated guesses, however.

    The Cassini spacecraft is huge, and NASA proudly boasts about its size. It is very expensive. Many nations of the world are collaborating. The entire astronomical community has been waiting a long time with high expectations for this much science on one launch. Iím very excited as well. I canít wait to see the close-up results from Saturn, shown to the world on JPL web sites, as they are doing for the marvelous Mars Pathfinder mission. So there is an enormous amount of money, and sweat equity, invested in the Cassini mission. Of course, for purely political reasons, the government and NASA will be inclined to do just about anything to keep it from being stopped.

Ross McCluney


Closing Remarks, Rollins College, Winter Park, 3 October 1997

When I reflect on how NASA and the U.S. government could have gone so wrong as to put massive nuclear material in space, I come to several conclusions.

A glimpse of the problem is found in a recent issue of Science magazine. Speaking of the huge 3.3 billion dollar Cassini mission to Saturn, reporter Andrew Lawler writes, "It was thought up in the early 1980s and proposed in 1989, yet its first data wonít arrive until 2004.... One researcher likens participation in the huge team of scientists and engineers involved in such projects to Ďentering a black hole.í And those who designed the experiment often played no role in analyzing the results. ĎThatís unhealthy,í says Bruce Murray, a planetary geologist with [Caltech] and former JPL Director. ĎScience is about building an experiment and interpreting data. What we had was a bureaucracy doing science. Very few people could participate.í"

I would say that this is really bureaucracy mimicking science, not doing it. This is science as economics. Not science as science.

What we are seeing here is a failure of vision, a failure to think at higher levels, seeing the connections of what we do to everything else. When you get stuck thinking at the level of monolithic, seemingly unconnected goals or tasks, or specific scientific questions, or specific spacecraft subsystems, their connections to the rest of the world are obscured or go unnoticed.

Itís this kind of thinking that allows chemical companies to dump relatively modest amounts of toxic wastes into a nearby pond, to avoid or reduce disposal costs and increase profits, and to do so for years, until one day it is discovered that the pond has become excessively polluted and threateningly toxic. Itís also the kind of thinking that allows NASA to put a large amount of radiotoxin on an excessively large and complex space probe.

If policy makers, such as the owners and executives of the chemical company, or NASA planners and administrators, were to think at higher levels, they could see their operation in a larger context. They would see the Earth and its human and non-human inhabitants around them, and they might realize the dangers inherent in their chemical waste dumping or in their launching radioactive material on failure-prone rockets through the Earthís atmosphere.

As I look at the Cassini probe, I see it as a symbol for the nuclearization of NASA. I think about the larger issues, and it seems clear that the real problem is just what the critics have been pointing out for some time: NASA is overdue for some creative thinking on its overall role in our government and its future "mission" for the U.S. people.

When you have a failure of high-level thinking amongst the planners and policy makers in a large government agency, often the bureaucracy takes over, quality suffers, the industrial bottom feeders move in to reap profits for little or modest work, and the whole enterprise stagnates.

Where Cassini went wrong, and indeed the whole of NASA as well, was to allow their industrial and military partners too much influence over their operations, perhaps even duping a few scientists into thinking that bigger, slower, nuclear is the best way to go. I say "duped" because Iím sure the corporations that built Cassini were, or will be, paid in full regardless of what happens. So in a real sense, they could care less if one Cassini fails or succeeds. The scientists, however, have a great stake in the success of the endeavor, but donít directly reap the enormous profits the aerospace companies invariably do with these mega-programs.

The Cassini launch is a tragedy for all living things in general on this planet which are put at risk by it, and all future launches of nuclear materials. It is also a risk for the scientists who bought into the program many years ago, and for NASA itself, which is putting its very future at risk in proceeding with this excessively expensive and dangerous mission.

To paraphrase Nobel Prize physicist Hans Betheís words to President Clinton this year on nuclear weapons research, I claim that the U.S. should not fund even creative thought on the nuclearization of space. [4 minutes speaking time.]

Ross McCluney


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