41–50 of 75 posts
Earlier quoted context omitted.
Which in this case would just be an incredibly strong magnetic field...
What about neutral particles?
So basically your spaceship needs to have the core part in a spinning sphere generating such a magnetic field. Also not to forget the gravitational attraction which would make the free particles in space quite attracted to your bulk spaceship, following you like mosquitos :).
That's okay, there's time to work on the shielding. 0.03 c is the most that can be feasibly achieved using top-end near future technology like dusty plasma fission fragment rockets. https://en.wikipedia.org/wiki/Fission-fragment_rocket
Thermonuclear pulse propulsion (a la Project Orion) can do better than that- up to 0.1c. And that requires no unproven technology; just a lot of money and a lot of politics (and a lot of fission fuel to buy with that money; I dunno if it's more than you could actually get on the market or not, but it would definitely cost A Lot).
FTFY
Why not use the speeding hydrogen in a nuclear reaction that fuels the ship, thereby killing 2 atoms with one stone? See http://en.wikipedia.org/wiki/Bussard_ramjet
The article points out some reasons why it might be difficult (not impossible!) to construct the electromagnetic field required for such a ramjet, but yes this point seems to be completely lost on the author. A Bussard ramjet specifically exploits the presence of interstellar hydrogen as a valuable energy resource.
See http://www.centauri-dreams.org/?p=22115 for some pointers.
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.
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)
(http://orbitaldebris.jsc.nasa.gov/protect/impacts.html)
(http://orbitaldebris.jsc.nasa.gov/photogallery/photogallery....)
And some of the debris is quite large - (http://orbitaldebris.jsc.nasa.gov/photogallery/gallarypage/s...) (Is that tape inches?? So that lump is about 1.5 to 2 inches?)
There are existing projects researching near earth impacts from high speed objects (http://ares.jsc.nasa.gov/ares/hvit/problem.cfm) so maybe there's some trickle through to research between very fast craft and small objects.
Is this a reputable journal? It seems to be from the same publisher ( https://en.wikipedia.org/wiki/SCIRP ) as Advances in Pure Mathematics , which recently accepted a paper written by a random text generator.
Beall's List of Predatory, Open-Access Publishers includes Scientific Research Publishing on the list, saying "Do not do business with the above publishers, including submitting article manuscripts, serving on editorial boards, buying advertising, etc. There are numerous traditional, legitimate journals that will publish your quality work for free, including many legitimate, open-access publishers."
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.
Earlier quoted context omitted.
Alastair Reynolds describes ice shields in a lot of detail.
In Pushing Ice if I recall correctly. Fantastic novel, also discusses the threat of the EM spectrum being blue-shifted to harmful wavelengths.
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…
What makes you think they're red?
