STOP CASSINI Newsletter #38 -- September 5th, 1997

Copyright (c) 1997

STOP CASSINI Newsletters Index

Subject: STOP CASSINI NEWSLETTER #38 - September 5th, 1997


Congressional support for hearings grows and grows. Our understanding is that now at least five Congresspeople -- Lynn Woosley (first), Pete Stark, Ron Dellums, George Miller and Bernard Sanders -- are calling for hearings, and others are listening.

Sincerely, Russell D. Hoffman, Editor, STOP CASSINI NEWSLETTER

**** STOP CASSINI NEWSLETTER Volume #38 September 5th, 1997 ****
Today's subjects:

****** VOLUME #38 September 5th, 1997 ******

By Russell D. Hoffman
Copyright (c) Russell D. Hoffman


For once, I can write something about Cassini and know that much of the rest of the world has already heard this news. Cassini is probably going to be delayed by about 10 days (to around October 16th) because of a tear in the insulation. They have to demount the Huygens probe, clean it, and remount it, and this requires removing Cassini from the Titan.

The bottom line is that we get ten free days in which to inform the public of the truth. Lame reporting about NASA's latest Cassini problem on CNN and several other stations have at least finally presented Cassini to the world.

Virtually every report called the launch controversial -- as though this were common knowledge -- but few reports would even mention what the controversy is. The best news coverage I saw was from Speedvision's AVIATION WEEK news show, which simply stated the reason for the controversy -- more than 72 pounds of plutonium. They also, I might add, had some of the best SHRIMP BOAT coverage last week.

CNN reporting was typical of the spineless follow-the-leader reports that appeared on many stations, yet it pretended to give the opposition its due. Their report showed some NASA/DOE RTG explosion tests, some old protest footage against an earlier plutonium launch, and told us NASA had tested the system very thoroughly and that, in short, everything is okay. I hope to get a chance to do a more thorough critique of the CNN report soon, but I for one am thoroughly disgusted by what they did.



At 12:32 PM 9/4/97 KS wrote:
Any news on getting boats into the are to help stall the launch? According to the [current news reports], the launch window extends to Nov. 6 (15th at the latest). Has Greenpeace been contacted? This sounds like a job for the zodiacs.




Thanks for your email.

Someone from Greenpeace has declined to take part in the Shrimp Boat Protest. I don't think it's an official statement though.

Other than that, there is significant interest but of course the new schedule does muck up the protest schedule as well (NASA should be very pleased about that and I'm sure they are!).

I think the most important thing is that it be used prior to the launch to test NASA's mettle.

Will they publish the exact coordinates of the danger zone? What are the exact laws? Would ANY law need to be violated to carry out such a protest? What was the danger zone for similar rocket (Titan) launches? Why did NASA have to resort to dropping "please move" streamers instead of ordering the boats to move?

We are hoping that reporters and others will be asking these questions, and I and others are researching these issues, because right now it appears that such a protest could completely stop the launch (and all other launches that might occur at the same time, too) and yet not violate one single law. Pretty cool.

I'll be updating that story in future newsletters. I do not, however, plan to act as coordinator of such an effort. I don't think a coordinator is needed, really. Anyone with a boat can go do it and there are lots of boats (and submarines) in Florida! Anyway, I'm based in California, not Florida where it would probably be necessary to be to coordinate it. If invited onto a boat during the scheduled launch, I would of course accept the honor.

However if Congressional Hearings occur, I, for one, will drop all interest in any form of protest. Even if later, Cassini launches. That's just me, of course. All I want is a chance to ask NASA some questions, and get sworn testimony for answers. A chance to present the opposing scientists, Gofman, Kaku, Poehler, and others, and a chance to show the world that the opposition to this madness is comprised of good people with well-thought-out opinions.

A chance to show that the leaders of the pro-nuclear Cassini for what they are, too...

Russell Hoffman




...I wonder if you or any cc's can help me with one of the central questions from pro-nuclear people like Franklin Ratliff:

The 72 pounds of plutonium in Cassini is divided into dozens of pellets. The plutonium is plutonium dioxide (a hard ceramic) not metallic plutonium. Since it is an oxide it cannot burn because it is already burnt. Each pellet is inside an iridium cladding inside a carbon-carbon capsule inside a graphite impact shell inside a graphite aeroshell. Iridium has a melting point of over 4,000 degrees Farenheit and is one of the hardest pure metals known. Carbon-carbon is the heat shielding used on the really hot parts of the space shuttle skin as well as the lining of the space shuttle solid rocket booster exhaust nozzles. Graphite is used as the skin for fighter planes as well as the shell for racing helmets.


There is another (related) question from NASA's statement:

EPA's figures were not credible since NASA claims that it would be impossible for all the plutonium dioxide to be in respirable form.

Does that mean SOME PuO2 could be rendered into respirable form?




Regarding EPA's statement, yes, some of the plutonium can be released in respirable form, especially in a flyby reentry accident. Actually, hundreds or thousands of billions or trillions or some similarly huge number of particles. Kaku might do the math for us. I've made a few stabs at it in my newsletters... But here's what NASA says:

In the June 1995 EIS NASA "expected" about a third to incinerate into both chunks and a fine dust in a flyby reentry accident. (Ratliff is right, it doesn't actually burn. Melt is a better description.)

Of that third, from 20% to 66% would be in respirable particles (defined by NASA as under 10 microns in size). There would be, as Karl Z. Morgan put it, "a spectrum of sizes".

In the June 1997 EIS the percentage number was changed to about 3% (1.7 out of 54 GPHSs).

But note that NASA states (time and again) that the RTG technology is a stable, well-tested technology. On page 2-14 of the June 1995 EIS is says this:

"The GPHS technology is the culmination of almost 25 years of design evolution."

A full quarter century! Ah, well, maybe better make that 12 years. On page 2-20 of the same document (just 7 pages later) it says:

"Overall, DOE has spent more than 12 years in the engineering, fabrication, safety testing, and evaluation of the GPHS, building on the experience gained from previous heat source development programs and an information base that has grown since the 1950's."

(DOE owns all the plutonium NASA uses.)

12 -- or maybe 25 -- or maybe more -- years of experience, and yet a 1/3 failure rate was alright with them! They intended to fly after production of the June 1995 EIS. That is to say, their "Record of Decision" was that it was OK to fly. Then for the June 1997 SEIS they changed the release percentage to 3%--such a big change for such a "well tested" technology is absurd!

What actually causes the GPHS failure rate, of 1.7 (average) out of 54, or 1/3 of them, or whatever the actual rate is, is a variety of things, including mode of reentry of the probe (side-on spinning, tumbling, stable) and damage to the GPHS shells as the RTGs melt away and the GPHS units fall away by themselves. Also, if a reentry becomes inevitable for any reason, subsequent space debris collisions on the way in might cause additional releases.

There are many factors. Ratliff's scenario that this technology is so wonderful and effective nothing will go wrong is so absurd even NASA doesn't believe it.

The NASA numbers are guesswork based on the need to provide a number they claim is scientifically justified. But either number -- 1/3 or 3% of 72+ pounds of plutonium dioxide, is an unacceptable risk for the potential gain.

NASA should get out of the nuke business and get into the peaceful-uses-of-space business.

Russell Hoffman



FROM: Dietrich Fischer

September 5, 1997

Russell D. Hoffman, Owner and Chief Programmer

Dear Russell,

Thank you for supporting the STOP CASSINI Newsletter!

Here is my full correspondence with Beverly Cook. You are welcome to include it, or any part of it, in your newsletter.

With best wishes, Dietrich

At Robert Cherwink's suggestion on the abolition-caucus, I sent the following letter on August 25 to the six addresses listed, including Beverly Cook:

Dear Ms. Cook,

I am very concerned about the risk of the proposed Cassini mission to Saturn. It cannot possibly be worth the risk of contaminating our entire planet, or even part of it, with deadly Plutonium. It is my opinion that Cassini must be canceled, or at least postponed and redesigned to use solar panels rather than nuclear generators.

Sincerely yours,

Dietrich Fischer

On August 29, I received the following reply:

I appreciate this opportunity to respond to you directly on your concerns over the safety of the Cassini mission. I am responsible for the safe use of the radioisotope power systems to be used on Cassini. As background, I am a metallurgical Engineer, with 23 years experience in nuclear safety and research and development. I chose the field of safety as my career because I believe that all technologies should be used in a safe manner.

I am greatly dismayed that so much inaccurate and misleading information has been provided to the public concerning Cassini. This is a summary of some of the facts.

The characteristics of the materials used in the RTGs are well understood. The United States has used RTG systems for electrical power for spacecraft for 37 years. For example, the Voyager, Pioneer, Galileo, Ulysses, Viking landers on Mars, and the seismic stations on the moon were all RTG powered. Graphite materials have been used to protect the plutonium dioxide fuel on reentry since 1968, with several upgrades in the graphite material as new materials were developed. The iridium material that encases the plutonium oxide pellet has been used since 1976. Hundreds of tests have been performed under very well controlled and documented conditions to understand how these materials behave under all of the conditions that exist during accidents.

In addition, almost one hundred tests have been performed on the RTG hardware under a variety of explosion overpressure, solid propellant fire, impact and reentry conditions. The results of these conditions on the RTG pieces are well understood and have been well documented.

Accidents with launching spacecraft happen in a sequential manner. First there is an explosion in the air, then pieces of the space vehicle breaking up may hit the RTGs, then the RTG parts hit the ground, and then they may be exposed to a fire as the solid rocket propellant burns. An entire range of accident conditions have been tested, including sequential conditions, so that we understand the effects of the accident conditions on the RTGs. Therefore, the tests that have been conducted consider the outside protective block may have been removed by overpressure or fragment impact. The bare plutonium pellets are impacted against hard surfaces and exposed to fires with none of the protective graphite around them. The overall graphite blocks with the plutonium inside of them are impacted with the surface partially removed as it would be if the materials had reentered through the atmosphere.

The characteristics of plutonium dioxide are also well understood. Many tests have been performed to characterize how the fuel could break up under accident conditions. The plutonium is in a ceramic form, does not shatter into fine material, is extremely difficult to vaporize, and is contained in multiple layers of protective materials. It is primarily an alpha emitter, which means that the radiation emitted can be stopped by a piece of paper or by the top layer of skin. Plutonium is a hazardous material. It becomes a hazard to people only if it is inhaled in very small particles into the lungs and stays there. It is not the most toxic substance known. For example, botulism toxin and anthrax spores are at least 10 to 100 times more toxic per gram. The biggest misconception concerns the delivery of the plutonium. The material is not in a form that will be easily distributed to people during an accident. An example given to me is "if properly distributed (one gallon to each lung), the Great Lakes contain enough water to drown every human being on earth." Just as there is no distribution mechanism to distribute all of the water in the Great Lakes to all the lungs on earth, there is no mechanism to distribute all of the plutonium on Cassini to all the lungs on earth.

The Radioisotope Thermoelectric Generators (RTGs) that are to be used on Cassini have been designed with the full range of possible accidents in mind. As is always required for missions that will have RTGs onboard, the Department of Energy generated a safety analysis report that details the entire analysis of what would happen to the RTGs if an accident occurs. This analysis also describes the effects if any material would be released, including how it might move through the environment, using actual meteorological information from the launch area, and how it could affect the public and the environment. The Cassini safety analysis report is over 2 feet thick, and summarized the results of a safety analysis that took over 6 years to complete. This analysis was then reviewed by an interagency group of experts, with support from over 50 scientists and engineers from industry and universities. The analysis was finally provided to the Office of Science and Technology Policy for final approval from the Office of the President to launch nuclear materials. White House approval has been required for all prior 26 times that nuclear systems have been launched in the United States.

For Cassini, there is no launch accident condition that would release plutonium at altitude in the launch area (Florida) or anywhere on Earth if the spacecraft reentered from Earth orbit. Any releases on the ground, from unusual impact conditions, are expected to be small (less than 15 grams) with the land contamination very localized. There is no effect expected on human health.

The spacecraft will fly by Earth in August 1999 to gain speed to proceed on the trip to Saturn. The chance for the spacecraft to reenter on this "swingby" of the Earth is less than one in one million. This is less than the chance each year of a 1 mile diameter asteroid hitting the Earth. If the spacecraft reenters, some material could be released at very high altitude. The resulting dose to people would be more than 15,000 times less than the radiation dose that people normally get from natural background radiation. Some release could occur from impact resulting in a dose to people, if no action is taken to move people out of the impact area. Actions would be taken to protect people in the impact area, and clean up any released material.

I have tried to be open and complete in this information. Obviously, there are many details I could not include here. I believe that the Cassini mission is safe. I and my family intend to be at the launch. I am one of the first people that had to be convinced of this fact. I would not agree to the launch of this spacecraft if I did not believe it was safe. I suggest that you go to the Cassini home page for additional information.

On September 1, I sent her the following letter:

Date: 01-Sep-97 at 14:56
From: Dietrich Fischer


Dear Ms Cook,

Thank you for your detailed response to my concerns about the safety of the Cassini Mission with RTGs. I have no doubt that a 2 foot thick report about the safety of Cassini exists. Could you please answer one more of my questions: Why did NASA state (before the Challenger disaster) that the probability of a shuttle launch failing was 1 in 100,000? These calculations must be based on many assumption that it has not been possible to test in reality. Where are the several million space probes that have been on a fly-by of earth to prove that 1 in 1 million enters the atmosphere? Your theoretical report does not convince me fully, and it would not be accepted by any insurance company, who are the presumed experts in estimating risks, because they bet their money on it.

Please tell me how NASA arrived at the 1 in 100,000 estimate for failures of the shuttle.

Thank you very much,

Dietrich Fischer
Professor of Computer Science
Pace University

(For the abolition-caucus, I added a sentence in my letter that insurance companies base risk analyses only on time series, not on theoretical calculations, because the calculations could be wrong.)

NASA's claim of a 1 in 100,000 chance of a space shuttle accident, severely criticized by Richard Feinman who was on the commission investigating the Challenger disaster, is chronicled in Ike Jeanes' ( excellent book, FORECAST AND SOLUTION: GRAPPLING WITH THE NUCLEAR, A TRILOGY FOR EVERYONE (Blacksburg, VA: Pocahontas Press, Tel. 1-800-446-0467, $25).

I hope this helps.
With best wishes, Dietrich



This is terrific stuff and I will use it completely unedited in the next newsletter!

I have already written a document just a few hours ago that does respond to similar sorts of statements about how safe the RTGs are [The Ratliff answer, shown above.] I'll forward it to you next and include both in the next newsletter. [Note that Beverly Cook gives new figures for the age and history of the RTG technology.)



END OF RESPONSE ******************************



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