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Highly relativistic spaceflight would be fatal for passengers and instruments

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Re: Highly relativistic spaceflight would be fatal for passengers and instruments

#31

Post by steve19 »

linuxhansl wrote: post #24

There's also the risk of hitting small dust particles, etc. A quick back of the envelope calculation reveals that hitting a spec of dust that weighs just 1 ug (a millions of a gram) at 90% c produces ~36 mega joule. Not a huge amount of energy (about the energy of burning 1kg of coal), but still. Hitting a grain of sand (10mg) at 90% c produces ~360 giga joule (energy of a small lightning)

That's the energy of about 20,000 rounds of 5.56mm NATO. The real problem is that it would be concentrated on such a tiny part of the spaceships hull.

Re: Highly relativistic spaceflight would be fatal for passengers and instruments

#33

Post by BjoernKW »

I can't help thinking that statements like these are merely meant to bog us down. I've heard and read statements like 'Interstellar travel isn't possible.' or my favourite 'We've enough problems down here on Earth already so let's forget about the more visionary ones altogether.' since the eighties.

I mean, why does one become a scientist if one doesn't at least have some greater vision?

This kind of statement seems like conceding failure before even having tried.

Re: Highly relativistic spaceflight would be fatal for passengers and instruments

#36

Post by ars »

serfdomroad wrote: post #25
gliese1337 wrote: post #15

Earlier quoted context omitted.

Not necessarily. There are some interesting potential radiation issues with "warp drives" as well. For example, at the boundary of a warp bubble of the generally-Alcubierre-like variety, space is shearing / expanding such that virtual particle pairs are incapable of recombining, just like at an event horizon. That could potentially create a great deal of radiation draining energy from the warp field. Additionally, wh…

Do you have any other info/links on the problems associated with the Alcubierre?

> on the problems associated with the Alcubierre?

You mean aside from the fact that it doesn't exist?

It's a mathematical solution to some equations - it's not an actual physical thing.

Re: Highly relativistic spaceflight would be fatal for passengers and instruments

#38

Post by Nursie »

noonespecial wrote: post #12

There's one thing I never quite got about these speculations. When you consider a ship leaving a solar system and accelerating, and the speed gained turning the "ambient hydrogen" into deadly radiation, why does it always seem to assume that hydrogen atoms are just kind of hanging out at low velocities relative to the home solar system and only turn into a problem when the bald captain says "engage"? Its a big univer…

'a few rouge hydrogen atoms'

It's rogue. Sorry, pet hate, can't help myself. That and people typing 'tounge' when they mean tongue.

Re: Highly relativistic spaceflight would be fatal for passengers and instruments

#39

Post by lucian1900 »

celerity wrote: post #20

You know what else is an obstacle to relativistic spaceflight? Being able to do relativistic space flight. Fun fact: people realized this a long time ago, and proposed different "shields" in front of the ship (it turns out that the most effective shape is a smoothed-out cone [of ice, say] -- see Asimov's Song of a Distant Earth).

Alastair Reynolds describes ice shields in a lot of detail.

Re: Highly relativistic spaceflight would be fatal for passengers and instruments

#40

Post by ekurutepe »

Reminds me of how the experts argued that the passengers would die of suffocation, if trains were to go faster than 50mph, back in the 19th century.

If we could figure out how to approach light speed, I'm sure we can also figure out how to shield people and electronics from harm.

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