Myth Busters is doing a show on the Moon Landing.

Oh, right. I forgot. Test pilots, mountain climbers, speed record setters, and other people pushing the boundaries of the possible never experience luck (good or bad).

Your taking that quote a tad out of context no? "I'm not sure how they managed to be so lucky" is quite a statement from some one funded by Nasa.

Oh, right. I forgot. Test pilots, mountain climbers, speed record setters, and other people pushing the boundaries of the possible never experience luck (good or bad).

Your taking that quote a tad out of context no? "I'm not sure how they managed to be so lucky" is quite a statement from some one funded by Nasa.


Not really. Manned flight is still one hell of a crapshot.
Two crews of the Space Shuttle would tell you that if they
could.

The guy was talking about the risks from radiation in space, not shuttle accidents!

The guy was talking about the risks from radiation in space, not shuttle accidents!



Dead is dead.

God, could we drop the rotating AC crap for once? Assuming the conversation started earlier in the thread is still going on, the point is that space travel is hazardous. So are many other things. That's one reason why people who climb mountains get respect; it's tough, (it's also expensive!) but it is also dangerous.

There is little intrinsic to the radiation hazard of space that makes it stand out. It isn't a messier death (than falling from five miles up, as did the crew of Challenger?) it isn't a less predictable hazard, it isn't a less well understood hazard. About the only thing that really comes to mind is that radiological hazards, like certain long-term chemical toxicities, can show up years later instead of, well, dying right then and there.

We continue to refine our understanding of all the hazards faced both in ordinary activities (say, driving), and extraordinary activities.

Again, look at mountain climbing. Everest was summited half a century ago. The "big wall" safety equipment and techniques (lead climbing, for instance) were developed extensively in the forties. When nylon and dynamic lines came along there were huge changes. The impact of sport climbing pushed gear manufacturers and international bodies (like the UIAA) to find new refinements in how to safeguard climbers. But, yet, the major manufacturers are still out there trying new ideas, new materials, stress-testing materials and systems and constantly learning just a little more about how to provide safety for this intrinsically dangerous activity.

So it can surprise no-one that NASA is investigating possible toxicity of lunar dust, the various radiological hazards of and on the Moon, and new techniques for abatement and avoidment of the various hazards. And it can be no surprised to anyone that the Moon Landings carried an element of risk -- and so will future missions.

The guy was talking about the risks from radiation in space, not shuttle accidents!



Dead is dead.

Of course Space flight is dangerous, but thats not the subject here, these eggheads are saying that Apollo was lucky in regards to radiation in space, so lucky that they are not sure how they managed it!
& yes it does surprise me that Nasa is yet to test moon samples for toxicity, considering they quarantined the crew's when they returned!
I'm not sure what a rotating Ac crap is, but i just found that luck statement strange, if you were "sick of it" you shouldn't have answered me.

Dont expect to have your question answered.
We are constantly told that without our atmosphere, magnetic field etc, life wouldn't be able to exist & earth would be a radioactive wasteland.But the moon that doesn't have the same defences isn't radioactive!(or has similar radioactivity to earth)

Dont expect to have your question answered.
We are constantly told that without our atmosphere, magnetic field etc, life wouldn't be able to exist & earth would be a radioactive wasteland.But the moon that doesn't have the same defences isn't radioactive!(or has similar radioactivity to earth)



Had to read this three times to unravel any of it.

A large part of the confusion arises from that word, "Radiation," which is used to mean two different things. "Radiation" is a property associated with radioactive materials, but not everything that radiates is radioactive.

Or, more accurately, ionizing. But this can be a subtle distinction. At the lowest end of the electromagnetic spectrum energy can still be transferred into matter. Microwaves are merely high-frequency radio, and they can cook a dinner in minutes if properly focused and tuned. Ordinary visible light can burn. The difference is, however, that when you reach the more energetic forms of light -- for instance, the short-wave ultraviolet -- this electromagnetic radiation has sufficient energy to break molecular bonds.

This is why ultraviolet light can bleach colors, even dissolve plastics, and of course damage skin cells leading to possible carcinomas.

Crank the energy a bit beyond that and you reach the energy level of Ionizing Radiation; which is to say, those photons now carry enough energy to break loose electrons and make ions.

(I am simplifying grotesquely here, of course. Most sources of electromagnetic energy give out a spectrum, and ionizing also occurs across a spectrum of weaker and stronger ionic bonds. Meaning that under the right conditions UV can do the trick.)

It is ionizing radiation that is capable of penetrating cells and damaging DNA, so it is that radiation we are most fearful of. But even here, much depends on the type, flux, energy level, and exposure time.

Your average chest x-ray, for instance, is significant to the organism but carries a very low risk factor -- unless you chose to repeat the exposure without leaving room for recovery. A series of twenty chest x-rays over a week is within acceptable risk. A series of twenty in the space of two minutes would not be.



But back to comparison of Earth and Moon. The most damaging element present on one but not the other is ultraviolet light. The harsh UV of our Sun, if not filtered by our own atmosphere, would almost literally rip apart simple organisms that did not have the protection of, say, the layer of dead skin we carry into the greatly attenuated sunlight down here.

Secondarily, there is a rather smaller amount of charged particles (mostly solar), and a great many of these are trapped by the Earth's magnetic field.

Thirdly, however, are uncharged particles -- gamma radiation and the like -- that ignore magnetic fields and punch through atmosphere (actually, again, I simplify; when a "cosmic ray" strike damages a micro-electronic junction, or a strand of DNA, it is as likely one of the lesser-energy products of an upper-air collision of some higher-energy extrasolar cosmic ray. At least, as I understand it!)

The Moon, of course, lacks a magnetic field. This means all these various particles are present -- as they are anywhere outside of the twin protection of Earth's atmosphere and magnetic field. Being on the Moon gives you some advantage as half the radiation coming your way is now blocked by the Moon itself. Unfortunately, it takes away somewhat by being able to spark secondary reactions. These reactions are similar to fluorescence; the secondary radiations occur only while the surface is exposed to external radiation, and ebb quickly when the external radiation is removed.

On the gripping hand, though, the lunar surface is not that effective at making secondary radiation in forms that are harmful to human beings. Standing around under a metal parasol would be much, much more dangerous.

Fortunately, again, much of these secondary radiations are of lesser power, and easier to block than the primary was. Radiation shielding against threats like this is designed like modern tank armor; first a hard layer that forces the incoming threat to break up, then a deeper but (relatively) softer layer to absorb the fragments.

(Perhaps a better example would be the micro-meteorite protection, which is almost identical; a thin carbon-fiber layer or similar to cause the meteorite to vaporize, then a layer of basically bulk padding to absorb the, well, plasma.



So, in short, neither Moon nor Earth can be described as a "radioactive wasteland," but without atmosphere an unprotected human will suffer severe sunburns and likely skin cancer in a handful of minutes. Without the magnetic field the incidence of charged particles goes up, leading to a greater amount of genetic damage (the flux is so small, even though the energies are much greater than that of visible light, that there is no gross effect).

The lunar environment can be described as having "radiological threats." But so can Earth; not only do we still get those energetic cosmic rays down here, but we also get sufficient UV to have to modify our behaviors accordingly (aka sunscreen, protective dyes in plastics, etc.) And we have a fair amount of natural radionuclides in our environment as well; uranium, radon gas, and so on.

The real question is one of degrees, and one of what protective measures are effective. Radiation is not an "all or none" qualification. The same sunny day is a pleasure to a tanned person, a danger to an untanned caucasian, and possible blindness, disfigurement, and death to an albino.

Characterizing the Moon as a "radioactive wasteland" paints it in colors that make it seem unsurvivable no matter what actions are taken. And this is not the case.

Heres a clue:Slow Barbeque Roll.What did they try to do with it?

On the gripping hand, though, the lunar surface is not that effective at making secondary radiation in forms that are harmful to human beings. Standing around under a metal parasol would be much, much more dangerous.

Nomuse or Nasa ?I know which one I would take to court.

Nomuse or Nasa ?I know which one I would take to court.


Yes, you've bolded the bit that says that it happens, which nomuse and I have not been disputing. But the point of what nomuse said is that it isn't as good at producing secondary radiation as a thin sheet of metal, for instance. You've missed his point. It's like if you quote a textbook that says that dysprosium or gadolinium are slightly magnetic, and someone responds that yes, it is, but nowhere near as much as, say, nickel or iron. If you then just requote the textbook bit about Dy or Gd and say "who are you going to believe", then all you have done is show that you aren't bothering to really examine what is being claimed.

How much secondary radiation is produced by the lunar surface in comparison to a thin sheet of metal? Do you know?

LEND will be able to detect neutron radiation emanating from the lunar surface and measure how energetic those neutrons are.

LEND will be able to detect neutron radiation emanating from the lunar surface and measure how energetic those neutrons are.



We can already detect them. In fact, neutron spectrometry has been used to learn more about the chemical composition and differences in various geographies of the Moon.

The main difference with LEND, besides a higher accuracy, is it also increases the detection spectrum; particularly, opening up detection of higher-energy neutrons.

The main difference with LEND, besides a higher accuracy, is it also increases the detection spectrum; particularly, opening up detection of higher-energy neutrons.


Email Nasa & tell them they are wasting time & money. Then ask them for a job.

Someone bring back the old hoax believers. These new ones are too damned dumb.