Will NASA Ever Recover Apollo 13's Plutonium From the Ocean 263
An anonymous reader writes "'Houston, we've had a problem,' said astronaut Jack Swigert on April 13, 1970. But the problem wasn't as simple as three astronauts potentially trapped in the void of space, 200,000 miles from Earth. The catastrophic risk came from the SNAP-27 radioisotope thermoelectric generator (RTG), a small nuclear reactor that was going to be placed on the moon to power experiments, carrying Plutonium 238 in Apollo 13's lunar module. As luck would have it, NASA had experience losing RTGs – a navigation satellite failed to reach orbit in 1964 and scattered small amounts of plutonium over the Indian Ocean. The SNAP-27 had been engineered to make it back to Earth intact in such an incident. The plutonium, like the astronauts, apparently survived reentry and came to rest with what remained of the lunar module in the Tonga Trench south of Fiji, approximately 6-9 kilometers underwater (its exact location is unknown). Extensive monitoring of the atmosphere in the area showed that no radiation escaped."
No (Score:5, Informative)
6Km under the ocean is probably the safest place for it.
There was concern at the last minute! (Score:5, Informative)
Pu238 not for bombs (Score:5, Informative)
The Plutonium 238 is suitable for RTG (radioisotope thermoelectric generator) but not for bombs.
Maybe this info will spare us most "nuke" posts (terrorist jokes, etc).
Small potatos compared to.... (Score:5, Informative)
Re:No (Score:5, Informative)
No, a ROV that works at shallow depths is easy. One that will work with the pressures sustained at the depths this thing is lying at is a WHOLE other story.
For example, at these kinds of pressures, the epoxy will crush, which will crush the battery. Similarly, any cameras are likely to have their optics destroyed by pressure differentials unless specifically designed for deepwater operation.
Re:wtf? (Score:5, Informative)
Anyway, if it was in the LEM, did the LEM even survive rentry? Since it had no heat shield, etc.? Is the LEM still attched to the CM during re-entry even? Pretty sure it's not.
The LEM was attached to the CM until just before re-entry; the SM was separated from the CM before the CM separated from the LEM, since the LEM was providing most of the life support and the SM was just dead weight. The LEM was not designed for reentry and burned up, but the RTG itself was designed to survive accidental reentry intact and is probably sitting on the sea-bed somewhere.
Re:Why would they? (Score:5, Informative)
This is on Cohen's wikipedia page:
When Ralph Nader described plutonium as "the most toxic substance known to mankind", Cohen, then a tenured professor, offered to consume on camera as much plutonium oxide as Nader could consume of caffeine,[17] the stimulant found in coffee and other beverages, which in its pure form has an oral (LD50) of 192 milligrams per kilogram in rats.[18]
Pu-238 is not fissile... (Score:5, Informative)
Not if the mermen militarise the plutonium and use it against the land people.
They're vicious SOBs down there.
This may be a joke, but it is worth pointing out that the Plutonium used in RTGs is not fissile, and can't be used to make bombs. Pu-238 [wikipedia.org] is only useful for RTGs. The isotope used in bombs is Pu-239, which is a common product of Uranium based reactors.
Producing Pu-238 is actually very difficult, as described in the above link. Unfortunately, the worlds supply is dwindling, and this endangers many upcoming space missions. One attractive option for creating more is to use Liquid fluoride thorium reactors [wikipedia.org], where Pu-238 is one of many useful products [flibe-energy.com] created.
This isn't the one that worries me (Score:5, Informative)
Rather, it's the SNAP reactor buried in an avalanche at the headwaters of the Ganges river.
Autumn 1965 [isu.edu]
"a small leak" (Score:2, Informative)
The snap-9a accident was not a small leak.
http://en.wikipedia.org/wiki/List_of_military_nuclear_accidents [wikipedia.org]
Indeed NASA (in the 1995 Cassini FEIS)[35] indicated that the SNAP-9a plutonium release was nearly double the 9000Ci added by all the atmospheric weapons tests to that date.[40][41]
1 pCi exposure typically will kill in 10^-8 of cases, but there were 9000^12 pCi dispersed by SNAP9. You can take any view you like about how many of them have actually been exposed to humans.
Re:Why would they? (Score:5, Informative)
Because people believe the media's saber rattling and they believe Ralph Nader who said that plutonium is “the most toxic substance known to mankind.” Even though it isn't. It's just too bad Ralph didn't accept Dr. Bernard Cohen's challenge to ingest equal amounts of caffeine to plutonium.
You do realize that this RTG is powered by Pu-238, which is *completely* different from the Pu-239 found in fission reactors?
Pu-239 is mildly radioactive. Maybe you wouldn't have ill effects from eating chunks of the ceramic oxide and pooped them out within a day or two. (Notice that he didn't offer to eat it in a bioavailable form. That's kind of like claiming that chlorine is always safe because it's in table salt.)
Pu-238, OTOH, is hundreds of times more radioactive, and it glows red hot. That's a whole other ball of wax.
So please, before you go around accusing people of being idiots, get your own facts straight.
Re:No (Score:5, Informative)
Re:Pu238 not for bombs (Score:5, Informative)
Actually, while the picture conjured up by "nuclear reactor" is ludicrously inappropriate to this device, the term per se is not actually incorrect usage. The Pu-239 undergoes alpha decay in the device, which is, after all, a nuclear reaction.
'The often-quoted idea that "nuclear reactions" are confined to induced processes is incorrect. "Radioactive decays" are a subgroup of "nuclear reactions" that are spontaneous rather than induced.'
http://en.wikipedia.org/wiki/Nuclear_reaction [wikipedia.org]
Re:Pu-238 is not fissile... (Score:5, Informative)
This may be a joke, but it is worth pointing out that the Plutonium used in RTGs is not fissile, and can't be used to make bombs. Pu-238 [wikipedia.org] is only useful for RTGs. The isotope used in bombs is Pu-239, which is a common product of Uranium based reactors.
Producing Pu-238 is actually very difficult, as described in the above link. Unfortunately, the worlds supply is dwindling, and this endangers many upcoming space missions. One attractive option for creating more is to use Liquid fluoride thorium reactors [wikipedia.org], where Pu-238 is one of many useful products [flibe-energy.com] created.
It's also worth noting that you're talking about nuclear weapons. It can be used to make "dirty" bombs [wikipedia.org], however.
Re:You have got to be kidding me (Score:5, Informative)
PU 238 doesn't undergo fission and doesn't release neutrons. The decay chain is almost all alpha particles (non radioactive helium and blocked by your skin. There are some very rare decays that could produce neutrons but not in any meaningful number.
Pu 238 -> U 234 + alpha (h/l 100 years)
U 234 -> Th 230 + alpha (h/l 250,000 years)
Th 230 -> Ra 226 + alpha (h/l 75,000 years)
Ra 226 ->Rn 222 + alpha (h/l 1,00 years)
Rn 222 -> Po 218 + alpha (h/l 4 days)
Po 218 -> Pb 214 + alpha (h/l 3 minutes)
Re:Why would they? (Score:4, Informative)
Kinda like Thomas Midgley Jr's [wikipedia.org] public demonstrations on how safe leaded fuel is...
On October 30, 1924, Midgley participated in a press conference to demonstrate the apparent safety of TEL. In this demonstration, he poured TEL over his hands, then placed a bottle of the chemical under his nose and inhaled its vapor for sixty seconds, declaring that he could do this every day without succumbing to any problems whatsoever.
After his hiatus to recover from lead poisoning...
In 1923, Midgley took a prolonged vacation to cure himself of lead poisoning. "After about a year's work in organic lead," he wrote in January 1923, "I find that my lungs have been affected and that it is necessary to drop all work and get a large supply of fresh air." He went to Miami, Florida for convalescence.
Maybe (Score:5, Informative)
I'm a nuclear engineer.
These things are not cheap. We have recovered one from the ocean floor before to fly it on a later mission. (albeit, the relative shallows of the florida coast.) If its possible to build a remote sub that could find it, I would bet the cost of recovery would be less than the cost of manufacture. (radar, sonar? how many right angles are on that thing? HOW would you find it?)
Its not dangerous. PU-238 cannot be used to make weapons.
Ref:
http://www.ne.doe.gov/space/neSpace2c.html [doe.gov]
---
SNAP-19B2
Nimbus-B-1
Meteorological
18-May-68
Status: Mission was aborted because of range safety destruct. RTG heat sources recovered and recycled.
---
Re:Why would they? (Score:4, Informative)
That is kind of missing the point. The point isn't that Plutonium is nontoxic, it's that it isn't significantly more toxic than a variety of other common substances. If you ingest 50 grams of caffeine, you will die. That amount of Plutonium is not likely to do you any good either, but it's pretty hard to get much worse than "this will kill you." So if you don't like Plutonium then you need a better argument than "it's toxic," because we don't ban things from the world just because of that.