> Dose rate matters. Particle type matters. Direction matters. Shielding matters.
There's an old story where a professor quizzes his physics class about how to most-safely distribute different kinds of radiation sources. A common variation involves three baked cookies, emitting alpha particles, beta, and gamma respectively. One must be eaten, one must be held in your hand, and one must be placed in a pocket.
A hint, and what I think is the interesting part of the answer, involves the idea that a victim is a lot like shielding. Things which are difficult to block are also things that are less-likely to stop and ruin your day.
Are we protecting the person with the cookies, or everyone else? I'm struggling to think of the best answer
Alpha: In the hand held away from the body would be reasonably safe. In a pocket of a lab coat might provide a little more shielding from the body with the coat material, but it is physically closer. Eaten would be very bad for the user, but protect the outside world the best
Beta: Medium penetration, would likely not be safe in any of these three situations
Gamma: High penetration, definitely not safe in any of these situations, best would be to get it as far away from you as possible, so held at arms length would mean you might only get high radiation exposure in your hand. Hospital visit is probably needed in any of these three situations
* Alpha in hand. Eaten, the "shielding" that blocks it will actually be very active living cells, leading to severe health outcomes. Your external layers of dead skin cells will be be fine, putting it in your pocket would be excessive.
* Gamma in hand, because whether it's in your hand or in your pocket, it's roughly the same risk, and most of it is actually going through you without stopping to have an effect. (Compared to other two.)
* Beta in pocket, where the additional clothing layer(s) offer some meaningful protection compared to your hand.
The "twist" behind the exercise involves how people often assume penetrative power is proportional to danger, when in some ways it's really the opposite. (Consider the danger profile of neutrinos.)
I guess in that case it would be to eat gamma? Assuming you're keeping all three long-term, the gamma particles will be washing over you whether they're inside you or out.
You're quite correct, the light of the morning and flu-medicine what I should've written is:
* Gamma is [eaten], because whether [wherever it is], it's roughly the same risk, and most of it is actually going through you without stopping to have an effect. (Compared to other two.)
Naturally there's a whole bunch of unstated "all else being equal" going on, where no cookie's' elements are extra-likely to be permanently incorporated into your bones versus excreted, etc.
Sure, using the ambiguous wording to assume the cookies all have such a large activity they are unsafe no matter how they are stored is technically a solution. But it's equally possible the teacher is imagining the cookies as only slightly radioactive such that it is indeed possibly to safely store them according to the alternatives given if you choose the correct pairs.
Eat the gamma, pocket the beta, hold the alpha. Nothing in the picture here stops gamma rays so it doesn't matter what you do with those; skin will stop alpha particles, but so will mucosa (and you die of that); in your pocket, the beta source will spall X-rays off your trousers at least some of the time so the beta burns will be mitigated.
I enjoy how moon-landing deniers will use the van Allen belts as a reason for why the astronauts could not have made it to the moon because of radiation exposure. Like, you don't believe NASA that they went to the moon, but you believe NASA that the van Allen belts exist?
People live in regions far more radioactive than the van Allen belts for far longer than the amount of time the Apollo and Artemis astronauts spent travelling through.
Strictly speaking, their existence was verified by Sputnik 2 (though the Soviets only released data on it after the fact, corroborating data from Explorer 1), so if you have a highly _specific_ conspiracy theory, around NASA rather than space stuff in general, that _could_ still work, I suppose?
I'm not disputing that conspiracy theorists tend to lack rigor but there is a full spectrum of positions between "space is fake" and "one specific extraordinary achievement with high incentive to fake it is fake".
I thought one of the things with New Space is that Commercial off the Shelf parts were being used more and more. I’m assuming if that’s a case there have been more mishaps.
How does SpaceX tackle this with both the rockets, and the thousand of Starlinks.
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> Dose rate matters. Particle type matters. Direction matters. Shielding matters.
There's an old story where a professor quizzes his physics class about how to most-safely distribute different kinds of radiation sources. A common variation involves three baked cookies, emitting alpha particles, beta, and gamma respectively. One must be eaten, one must be held in your hand, and one must be placed in a pocket.
A hint, and what I think is the interesting part of the answer, involves the idea that a victim is a lot like shielding. Things which are difficult to block are also things that are less-likely to stop and ruin your day.
https://ocw.mit.edu/courses/22-01-introduction-to-nuclear-en...
Alpha: In the hand held away from the body would be reasonably safe. In a pocket of a lab coat might provide a little more shielding from the body with the coat material, but it is physically closer. Eaten would be very bad for the user, but protect the outside world the best
Beta: Medium penetration, would likely not be safe in any of these three situations
Gamma: High penetration, definitely not safe in any of these situations, best would be to get it as far away from you as possible, so held at arms length would mean you might only get high radiation exposure in your hand. Hospital visit is probably needed in any of these three situations
Pocket the beta emitter, a little bit of shielding will make a big difference.
Hold the alpha emitter, if you hold it with just a pair of fingers you will be able to reduce you dosage a lot compared to holding it tightly.
* Alpha in hand. Eaten, the "shielding" that blocks it will actually be very active living cells, leading to severe health outcomes. Your external layers of dead skin cells will be be fine, putting it in your pocket would be excessive.
* Gamma in hand, because whether it's in your hand or in your pocket, it's roughly the same risk, and most of it is actually going through you without stopping to have an effect. (Compared to other two.)
* Beta in pocket, where the additional clothing layer(s) offer some meaningful protection compared to your hand.
The "twist" behind the exercise involves how people often assume penetrative power is proportional to danger, when in some ways it's really the opposite. (Consider the danger profile of neutrinos.)
* Gamma is [eaten], because whether [wherever it is], it's roughly the same risk, and most of it is actually going through you without stopping to have an effect. (Compared to other two.)
Naturally there's a whole bunch of unstated "all else being equal" going on, where no cookie's' elements are extra-likely to be permanently incorporated into your bones versus excreted, etc.
The radiation that passes through is not the problem.
Like, for example, people who live in Aberdeen.
How does SpaceX tackle this with both the rockets, and the thousand of Starlinks.
> Artemis II and the invisible hazard
Decent Harry Potter book title