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Nuclear 'Asteroids' Due In A Few Hundred Years
easyCoder writes "In this space.com article, it mentions a RORSAT satellite that has been leaking radioactive coolant, leaving little droplets of it in orbit around our planet. However, further down, it also mentions this, quoted here for maximum impact: 'After a RORSATs tour-of-duty was over, the reactor's fuel core was shot high above Earth into a "disposal orbit." Once at that altitude the power supply unit would take several hundred years before it reentered the Earth's atmosphere.' Wow. So ... our great-grandchildren can expect a lovely day, partly cloudy with the occasional nuclear reactor plummeting down from outer space."
Not that it matters much what an asteroid is made of when it's landing on you.
Or 1978.
The article isn't worried about the radiation from the drops of coolent, they are worried that, as the collent falls back to earth, it could impact other sats causing a cascade that would destroy a large chunk of the sats currently around earth. And in the process render space a much more dangerous place due to the extra space junk that would be released.
A meteor is the flash of light that a interstellar object causes etering out atmosphere,the stuff going through the atmosphere is called meteoroid if it vapourizes before hitting the ground, or if it lands its called be a meteorite.
not quite, although the term asteroid is in fact incorrect because asteroids are strictly considered to be objects from the asteroid belt between mars and jupiter. Meteors is probably the closest term, but again this is something manmade so calling it by it's name is probably the best term but if you had to use something probably meteor or meteorite
You win battles by knowing the enemy's timing, and using a timing which the enemy does not expect. Miyamoto Musashi
Do a search for "Cosmos 954" It still had its power source when it hit Canada in 1978. And yeah, I'm not worried either. The stuff spread over a wide area, and as my Dad was tought in the '60s, the solution to pollution is dilution.
And just as junk emails cause a threat to network connectivity, space junk can potentially damage future space missions. NASA constantly keeps its eye on the movements of these bits of space trash.
space.com has a comprehensive list of space junk items, and who put them there.
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Nothing to see here
A Big Piece of Garbage
At least quote it correctly:
Student: So when is this 'snake act' supposed to occur?
Archeologist: Well... if this is the 5, and this is the 1, every five thousand years.
Student: So... I've got some time....
Learn something new.
There is also a difference between having the suns radiation hit your skin and breathing radioactive material that bond to the calcium in your bones delivering a 24/7 does of radiation to a single spot.
You can stand on a floor of strontium 90 every day and not really be affected (well, I think there are parts of your skin thin enough that the radiation will cause problems), breath a few particles of it and some Bad Things will happen.
I think the stuff talked about here make strontium 90 look good. Some of that stuff takes VERY little though yellow and magenta chains grant immunity to radiation (Ok, inside joke, govt labs use yellow and magenta plastic chains to rope off radioactive areas with no other explaination leaving you wondering what the actual contamination is from. Nothing like a 2 foot square hole in the hall in front of your office with one of those chains around the very edge of the hole).
------- Sorry about the spelling, I suffer from two problems. Dyslexia makes it difficult to spell well, lazy makes it
You have to remember the enviroment that produced this mess.
The former soviets had a very cavalier attitude towards radioactivity. Part of the problem was the extreme pressure they felt to keep up with western technology.
The soviets have radioactive waste everywhere. Not just Chernobyl, but across the continent.
It really is a severe problem. There are also over 40,000 barrels of waste in the Barents sea that need to be cleaned up before it kills the fisheries.
This doesn't mention all the nuclear accidents that they had that released radioactivity in the enviroment. Many of which were never published or covered up. The only reason we learned about Chernobyl is because fallout reached Sweden.
BTW, the Chernobyl sarcophagus is crumbling, and threatens to expose the radioactive core once again, unless western nations fund some fix. So that mess is not over yet.
"Radioactive Mess" would be Russia's middle name if it had one.
Take the cheese to sickbay, the doctor should see it as soon as possible - B'Elanna Torres, "Learning Curve"
As long as we are not talking about things like Plutonium 238, I think we are still safe.
These droplets will quickly burn as soon as they enter in the atmosphere since Na and K are highly reactive. Both the sodium and potassium will absorb CO2/H20 becoming small crystals of inoffensive carbonates. The most dangerous compound coming from this Na/K coolant might be Argon-39 (released from the radioactive Sodium-24).
Now, Argon-39 has a beta-decay mode, with around 300 years half-life. First, beta-decay is one of the least dangerous types of decay. For example, tritium is much more dangerous than Argon-39 since it has a half-life of only 10 years. But tritium is used everywhere today, in exit signs for example, or other "glow in the dark" toys. You can order this stuff on the Internet today...
Don't try to use the force. Do or do not, there is no try.
A missile silo doesn't move around much, and it's hard to keep completely secret. The Soviets knew exactly where every one of them was and had several nukes pinpointed on each one.
In the oceans, however, are ships and submarines which also carry nuclear weapons. Ships do move around, and it's relatively easy to keep the movements of a ship at sea secret. The Soviets needed to know where the US was keeping its seaborne nuclear assets, so that they could be eliminated before they could launch in the event of World War 3. In addition to (IIRC) around half of the American arsenal, _all_ the British nukes and most of the French ones are on submarines.
I'd say the Soviets had a damn good reason to be keeping a close eye on the oceans.
Real Daleks don't climb stairs - they level the building.
This Soviet Union placed a series of radar-equipped ocean reconnaissance satellites, known as RORSATs in the west in low Earth orbit beginning in 1967. Employing powerful radars and working in pairs, they located and targeted U.S. ships for destruction by Soviet naval forces...
Stay sentient. Don't drink bad milk.
The fuel was U-235. Half-life 704 million years, resulting in a chain of 10 other radioactive elements (excluding branches) before stopping at stable Pb-207. And that's just the original fuel, not fission by-products. A veritable nuclear cocktail.
Going at a large velocity a 3inch diameter sphere of coolant will do some damage (possibly quite serious), and that's what has people worried. It certainly has the potential to change the orbit of one of the smaller satellites.
Operating a radar took a lot of power, more than you could get from solar panels or an RTG.
>I do have one question about the physical properties of the NaK coolant: what is its vapor pressure?
Pretty low. To get a vapor pressure of 1 mm of mercury, you have to heat it to 355 C.
31 kg of 90% U235.
n t/rorsat.htm
Reference: http://www.fas.org/spp/guide/russia/military/sigi
There have been dozens of nuclear powered satellites launched by both USSR and USA. When the satellite reaches its end of life, the core is ejected into a higher orbit. The result of all this is there are several tonnes of nuclear waste and a few hunderd pounds of enriched uranium orbiting the Earth. You can read more about it here Nuclear Powered Space Missions
How much material are we talking?
According to "Der rote Orbit" by Harro Zimmer, a book on the Soviet space program based on data released in the 1990s: There is about 940 kg of highly enriched uranium and more than 15 tons of radioactive material. The sattelites will stay about 600 years in orbit before coming down. Argon-39, mentioned in the article, will still be around then.
One exception is Kosmos 1900. On this RORSAT mission the core ejection was done later than usual due to a technical problem. Since the orbit was already very low then, the core was shot to an altitude of about 750 km, where it will only last about 100 years.
Will this be a major event to the earth, or will the upper atmosphere just shrug and eat it up?
This is unclear. There were two incidents in the RORSAT history where the reactor core re-entered Earth's atmosphere. Kosmos 1402 did not leave a radioactive trace while the infamous Kosmos 954 spacecraft certainly did.
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However, argon is a noble gas that does not combine chemically with anything, so long-term exposure from absorption into the human body is not exactly a big issue. It also forms a small but detectable proportion (about 1%) of the Earth's atmosphere, so it will be diluted by a factor of billions or trillions to one.
Sodium of course is highly reactive. I assume that it's the K (potassium?) that decays into the sodium as Na = sodium already... nuclear science is not my strong suit unfortunately. Upon hitting the high atmosphere, sodium will combine rapidly, probably with hydrogen (NaH) or Oxygen (NaO2/Na2O/Na2O2) none of which are used by the human body... may be a problem if it recombines, but again we're talking minute quantities relatively speaking.
The coolant is all in the form of liquid droplets which will be showering down over the earth over a period of hundreds of years. To be honest I can't see what the big deal is here. Yes, there's radiation showering down, but these are *droplets*, they're not going to smack you in the eye - they will break up probably before they hit the stratosphere, let alone the troposphere.
The net effect will be an increase in background radiation levels too small to measure.
The original article focuses on the hazards of the droplets as space junk... which to me seems sensible. As an earthbound radiation source these don't figure. As space junk they present not only a collision hazard but a radioactive one.
I see what you mean. In this reference: http://www.basf.com/inorganics/pdf/bulletin/NaK_bu lletin.pdf it says that eutectic NaK (78% K, 22% Na) is liquid from -12.6C to 785C. That's a pretty wide range that helps explain its utility as a reactor coolant, and it also suggests a pretty low vapor pressure. Oh well.
Just in case you couldnt be bothered to track the flaw in this guy's argument, let me make it easy for you. His claim is that there will be a massive "die-off" when we run out of oil, and compares it to biological systems that face resource restriction. The flaw is that oil is not our only source of energy! Coal and natural gas can easily make up the energy differences and will last us quite some time still, so we arent going to go into energy starvation. Certainly there will be a change in the economy, as alternate fuels [note not energy sources] start to compete economically with gas as prices rise. So while the future is not all sweetness and light, its also not certain doom.
> The only reason we learned about Chernobyl is because fallout reached Sweden.
Hrm, Finland is between Sweden and Russia. It came here first. We noticed and reported.
Damn, we are not THAT small country. Linus was born here!
PS. US has it's share of missing nuclear/chemical weapons also.
Anything that has a halflife of 17 million
years isn't going to be particularly radioactive.
It will release a particle every now and then but
unless you build your house and everything in it
from that material, you should probably be more
worried about natural radon gas emissions.
sigs are hazardous to your health
I wish they said how many hundred years. While I am not familar with the RORSAT reactors, the waste from commericial nuclear reactors is as dangerous as the ore it came from in between 600 and 1200 years, depending on how you measure toxicity.
A man from Lockheed, whose nuclear space program is located in King of Prussia, PA, just gave a talk on this at Penn State to the Nuclear Engineering students. To clarify what is actually up there, there is 1 US RTG core, and about 35 Russian RTG cores (that we know of). RTG is a Radioisotope Thermoelectric Generator, they provide power for a very long time many times outlasting the life of the satellite. The reason we use these and not just solar panels has to do with harsh environments, and solar energy exponentially decays the further from the sun you get, once you get past Mars it is effectively zero. All the cores total about 1 Metric ton of highly enriched Uranium 235. The reason they are there is a simple one, when a malfunction happened on board a satellite the nuclear core was detached and shot off into a higher orbit. (on one occasion the satellite's guidance system was out and it actually sent the core crashing towards Earth. It landed somewhere in the jungle of South America, but the Soviets never found it, and refused our help.) So those cores are sitting up there in a high orbit and will come crashing down in about 600 years. As far as burning up in the atmosphere, well that was the methodology that NASA used to work with (now they are working with the idea that they should make the core indestructible and just retrieve it), however I am not sure and the man from Lockheed didn't give the impression it was. Personally I believe that's what we hope, but we just are not sure. Also, remember that we only have 1 core up there, the Soviets have 35 (at least) so who knows what to say about their cores.
It's happened more than you might think. There are problems with those satellites that use nuclear reactors and those that use radioisotope thermal generators (RTGs). From memory...
As for those returning to Earth...
There have been a number of launch failures.
The coolant spills have been seen from some of the later Kosmos reactors which have ejected their cores, so it appears to be a shortcoming in the design of the eject mechanism. The first signs of leakage came from Kosmos 1900 in 1997 - this is also a Kosmos which has failed to send its reactor into a high-level disposal orbit. Having said that, some 14 Kosmos RORSATs did successfully eject their cores between the first flight of the design in 1980 and the suspension of the programme in 1988.
NASA and the Air Force have tracked a number of satellites that have begun to disintegrate after many years in orbit. The cause of this failure is completely unknown, but amongst the ones that are known to have failed are the US SNAPSHOT satellite - the first to be flown with a nuclear reactor in 1965 that began disintegrating in the late 1970s, and Nimbus VI, launched in 1975 which appears to have completely broken up.
Kosmos 1461 appears to have exploded in orbit for no readily apparent reason. Kosmos 1900 is also stuck in a lower orbit that intended and will fall back to Earth before the nominal 600 year period.
Finally, there was the RTG from Apollo 13 which should have powered its Lunar experimental station, but remained on the Lunar Module which acted as a lifeboat for the failed mission. The LM disintegrated in the atmosphere, the RTG appears to have survived and crashed into the West Pacific. No radiation was detected.
Best wishes,
Mike.
They aren't meteor(ites?)s today, so no.
They don't need to be meteorites today. Since they are expected to be meteorites in "A Few Hundred Years", I think that the term is appropriate.
By your logic, a car can not be called a car, because in the past (before assembly) it was only a bunch of parts. Try to get it insured under that definition.
Exactly. Worldwide impact would likely be on the same order as a new gigawatt coal facility coming online without modern emissions controlls. What all the anti-nuclear people seem to miss is that there are only a handfull of instances where nuclear power facilities released measurable amounts of radioactive material, yet coal power plants (the ones most likely to replace nuclear due to abundant reserves) pour out literally tons of radioactive material every year!
There are 4 boxes to use in the defense of liberty: soap, ballot, jury, ammo. Use in that order. Starting now.
Unlike a chemical explosion, a nuclear explosion is rarely more than 10% efficient. Most of the fissionable material is not consumed in the nuclear reaction, instead it is vaporised into the environment. The vast majority of fissionable material ever used for explosions has been put into the atmosphere where it has gradually settled back to Earth.
Best wishes,
Mike.
Uh no, as the chain reaction starts, the other atoms in the core gain an enormous amount of thermal kinetic energy and the core attempts to vapourise. If it disperses, neutrons are far less likely to hit a nucleus and produce further fission events. If this process is allowed to continue fissile material is physically removed from the path of the neutrons - so some fissile material would never undergo fission.
The outward expansion of the core is unstoppable, it always disassembles the core before the reaction can run to completion - a matter of microseconds. The objective must be to stop the outward expansion of the core for as long as possible by producing an inward pressure of equal or greater force. So modern weapons use a heavy metal tamper around the core to provide a lot of inertia against expansion, and a huge amount of implosion pressure to counteract the outward movement of the core material for as long as possible.
I did some checking, Little Boy was 1.3% efficient, Fat Man was 16% efficient. Apparently normal fission cores are limited to around 25% efficiency, larger ones might be up to 50% efficient. Some of the later US tests that used so-called levitated cores got efficiencies up to 35% - which is pretty damn impressive - in a horribly scary sort of way.
Best wishes,
Mike.
While this is modded "Funny," your idea does deserve consideration. However, the problem with your idea is that it's impractical to power a very large satellite (the RORSAT is the size of a large bus with a huge radar set on one end) for any length of time on solar power alone. RTG's or full-up reactors are a must for this type of thing.
So, good suggestion, but not practical.
In the end they will lay their freedom at our feet and say to us, Make us your slaves, but feed us. - Fyodor Dostoyevsky