3, 2, 1 ... poof! Dusted!
Houston, you caused a problem!
Even as people in Japan experience "black rain" because of Fukushima, NASA is threatening a plutonium-laden "black rain" for Christmas.
Some time between November 25th and December 15th, 2011, NASA plans to launch a plutonium 238-laden rocket carrying a robotic rover named Curiosity, aimed for Mars.
Curiosity will be NASA' 27th nuclear space launch. Three have already failed, and failures are hardly a thing of the past, nor can they be, because of the debris field, and because everything we build, and do, is imperfect.
One of the three failed nuclear launches resulted in the INTENTIONAL (as in: "this is what WILL happen in an accident, and of course, there will be accidents") release of several POUNDS of plutonium (in 1964).
There were several other failures and countless near-misses, all in just 26 flights. We can't get lucky all the time, but luck is what NASA relies on to succeed. Dumb luck.
NASA hopes you won't get too curious about Curiosity. The robotic mission is extremely risky (as in: "will probably not achieve objectives due to critical failure at some point") and should be abandoned.
NASA's use of plutonium-238 (in dioxide form) for this mission follows a pattern of partial fixes to insurmountable problems with nuclear fuels.
After getting the idea for radioisotope-powered thermoelectric generators (RTGs) for space (and undersea) missions from the Russians, NASA's original "containers" for the plutonium were designed to simply vaporize their contents in most accident scenarios: In other words, there was virtually no containment whatsoever. The "theory" was that they would be extra-careful for those flights carrying plutonium, and wouldn't have accidents that way. It didn't work out. The other part of the "theory" was that by having the thermocouples right next to the plutonium, you could get more useful heat out of the unit -- and thus it was more efficient. More electricity could be generated from a given quantity of plutonium.
The theory "snapped" when a mission blew up during late launch, destroying the Transit Satellite and its SNAP-9A nuclear power unit, scattering its deadly contents, and causing a global, measurable increase in plutonium levels and -- according to eminent nuclear physicist and medical doctor John Gofman -- causing as many as one million additional lung cancers globally.
A single pound of plutonium could cause lung cancer in every person on earth if we each inhaled a little portion of it. And then it could do it again, and again. NASA is threatening to vaporize 10.6 pounds of plutonium into our fragile environment. We should stop them.
Admittedly, the "modern" containers for the plutonium are somewhat better than the old system. The new containers are designed to safely hold the plutonium in many potential accident scenarios -- but by no means ALL accident scenarios. In fact, during EVERY phase of flight while within earth's gravitational pull, plutonium can be released which will descend back upon us. In some phases of the flight, a complete release of the entire contents is practically guaranteed if an accident occurs!
The containers (there are dozens of individual plutonium-packages inside the single RTG on Curiosity) are designed to reduce the CHANCES of SOME TYPES of releases in FAVOR of increased QUANTITIES of released plutonium in case of other types of failure, especially late in the launch, or during a full-stack powered impact into the earth (something they have self-destruct mechanisms to avoid, but even self-destruct mechanisms have been known to fail at critical times).
There are many pathways to failure in this mission. For example, the additional weight of this new rover over previous, solar-powered units demanded a new method of landing on Mars -- the old one ("Bouncy Bouncy") was unreliable anyway. The new method -- a tethered descent -- is very difficult and is sure to be unreliable, too. If we were risking only money, I guess it wouldn't matter, although a few billion dollars could build a lot of schools and pay a lot of teachers' salaries for a while.
Instead, all that money might be wasted, and all that plutonium might be launched for naught -- hundreds of billions of lethal doses' worth of one of the world's most deadly poisons.
(Plutonium-238 is about 275 times more toxic than normal "weapons grade" plutonium (Pu-239), often cited as the world's deadliest substance. Pu 238's half-life, about 87.75 years, is correspondingly about 275 times shorter than Pu-239's 24,100 year half-life. A significant portion (about 10%) of the Pu is Pu-239 with its 24,100 year half-life.)
Thousands of people have already protested these dangerous nuclear launches. But to no avail. NASA's arrogant continued use of plutonium-238 for "civilian" space purposes appears to be directly related to the U.S. government's stated desire to launch plutonium and uranium-powered military rocketry for "domination" of outer space near earth. So there are some very good reasons to oppose THIS launch, besides that it's a waste of money.
The amount of space debris already in orbit guarantees that if nuclear payloads are launched, there will be catastrophic accidents, possibly over highly-populated areas. This launch could fail over a major city, causing massive evacuations and widespread contamination! It could start a war.
Hundreds of studies with animals (and a few that were done on humans) have indicated reliably that plutonium follows a "Linear, No Threshold" health effects pattern. So, if there's an accident, no matter where or how it comes down, it's bound to poison a lot of people before all the plutonium decays, and decays again, and again, finally into something stable.
This launch is anything but an engineering marvel. It is a potential engineering disaster. Anyone truly curious about it will surely be aghast, but forcing this risk on billions of unsuspecting humans (who are now breathing Fukushima's effluent as well) is especially cruel.
There is simply no sane reason for NASA to do this.
The author's prior comments on Cassini were published in Space News, The Washington Post and elsewhere. He is a computer programmer and co-author of Statistics Explained, a computer program which teaches first-year statistics for scientists. He is also the author of All About Pumps and the Animated Periodic Table of the Elements, and a co-author of The Heart: The Engine of Life, all computer programs. He has also authored a book about nuclear power called The Code Killers (2008).
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