4chan archive /sci/ (index)
2012-09-06 02:19 5031054 Anonymous (sand.jpg 200x191 11kB)
You are floating in space in your space suit. Doing stuff. And suddenly a grain of sand hits you at 0.999999c. What happens? I have heard various explanations ranging from 'nothing' to 'a nuclear explosion'. A particle weighing 1 milligram (about the weight of sand) and traveling at 0.999999c (299792158m/s) has about 62843400000000 joules of energy or 15 kilotons. At the same time, the surface area is tiny so not all of that energy will be distributed into your body. Or will it? Discuss.

0 min later 5031057 Anonymous
You die.

1 min later 5031061 Anonymous
it will likely just pas trough you making a tiny hole.

5 min later 5031071 Anonymous
You are vaporized and the matter of your body explodes outwards in a big shock wave.

5 min later 5031072 Anonymous
Well it's going to have a lot of momentum and when it has all got to go somewhere. It's also going to exert a lot of pressure when you collide, I'm going to say that it zips right through you and continues going.

8 min later 5031076 Anonymous
>>5031061 >>5031072 In order to pass through you, it would have to push the matter in front of it out of the way. This is also going to have ridiculous momentum, which in turn pushes stuff out of the way. In other words, shockwave. Which annihilates you.

11 min later 5031086 Anonymous
It's not just going to make a straight line through your body like a bullet. The forces between the atoms in the sand grain and the atoms in your body are much stronger than the forces holding the sand grain together. While you'll only absorb a small fraction of the energy of the thing, that will probably be more than enough to blow you to smithereens.

13 min later 5031090 Anonymous
>>5031076 >>5031076 Imagine firing a javelin through ballistics gel. Won't make a huge shockwave, it'll just pierce right through it and...oh, I see. This is going to be one of those frequently recurring /sci/ posts like the goddamn "Who Wants to be a Millionaire" thing and the "Will it take off?" threads. Fuck.

20 min later 5031102 Anonymous
>>5031090 But a javelin doesn't travel at relativistic speeds. Even comparatively slow objects like a 0.50 BMG bullet will shred a block of ballistics gel because of the cavitation it causes.

35 min later 5031122 Anonymous
The odds of it actually doing any damage to you are very tiny, even if it was on a direct collision course, because in one discrete fundamental unit of time it would have passed through a distance several orders of magnitude over your body's length.

40 min later 5031127 Anonymous
>>5031072 the momentum doesn't have to go anywhere it can stay with the particle

55 min later 5031147 Anonymous
>>5031122 So what happens to the atoms that it passes though? Why do atoms explode when they are collided at similar speeds in a particle accelerator, while the sand grain is unaffected?

1 hours later 5031191 Anonymous
It would break apart on your skin and the pieces would deflect off, flying in different directions

1 hours later 5031197 Anonymous
You'd become the Sandman.

1 hours later 5031217 Anonymous
I would have to say, and it is my expert opinion, that it would most likely seem as though nothing has happened at all.

1 hours later 5031218 Anonymous
You would turn into a black hole

1 hours later 5031252 Anonymous
>>5031054 https://en.wikipedia.org/wiki/Thermal_Micrometeoroid_Garment http://www.britannica.com/EBchecked/topic/139217/interplanetary-dust-particle-IDP https://en.wikipedia.org/wiki/Micrometeoroid#Effect_on_spacecraft_operations

2 hours later 5031297 Anonymous
>>5031122 That makes no sense at all.

2 hours later 5031303 Anonymous
Similar to this: http://what-if.xkcd.com/1/ In short, you're fucked. Spectacularly. It most definitely does not just pass right through.

2 hours later 5031343 Anonymous
>>5031147 When you collide nuclei together, you end up trying to tear quarks away from each other, but you can't -- the strong force is crazy strong would rather spontaneously generate more quarks, which then hadronize into all sorts of particles. So I guess it's kinda like a pinata that gives you more candy the harder you hit it.

2 hours later 5031377 ruski
>>5031122 I read about this somewhere. Time is not fluid, but closer to many "frames of life" per second. Any one have more info on this?

2 hours later 5031385 Anonymous
>>5031122 That is not true.

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