(October 20, 2015 at 1:00 am)vorlon13 Wrote: There are many problems with travel at +99%C.
The background radiation of the universe ahead of you will be extremely blue shifted and extremely dangerous.
Rocks and asteroids are few and far between, the bigger and much more frequent issue would be microscopic grains of dust. They will smack with astonishing, vicious energy and will be extremely dangerous.
Accelerating to that speed is extremely difficult. Even harnessing large nuclear explosives to propel a craft might be good for less than 0.1C. Even antimatter, unless used extremely efficiently won't do it. There is a concept called a Bussard Interstellar ramjet, and it actually gets more efficient the faster it goes, but it is extremely difficult imagining how to build one, let alone piloting it around the galaxy.
The Space Shuttle accelerated for 2-3 Gs for ~8 minutes just to reach 17000 MPH, to reach a high percent of C requires acceleration of 1 G for a year, or 2 Gs for 6 months, or 3 Gs for 4 months, it is difficult to even imagine getting up to those speeds, and then recall you also have to take fuel to decelerate at your craft at the destination.
You're better contemplating large multi-generational ships in the 0.05C range. Then large nukes can work, and actually work well. Preliminary designs and concepts were worked out in the 60's. If you're willing to spend ~400 years building it, a multi-generational craft capable of taking 50,000 people and the materials to provision a viable colony is possible. Refueling and refurbishing (or duplicating) the craft at the destination would take some centuries, and then one or more colonizing attempts could be made, assuming the first destination was well chosen.
That technology could be used to explore and colonize our galaxy in a couple or few million years.
The brussard ramjet is commonly discussed in older hard sci fi. One of the main issues with it is that it relies on a powerful magnetic field. In order to make possible for humans to be on it you have to create a bubble in field around the cab.
To-morrow, and to-morrow, and to-morrow,
Creeps in this petty pace from day to day,
To the last syllable of recorded time;
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life's but a walking shadow, a poor player,
That struts and frets his hour upon the stage,
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.
Creeps in this petty pace from day to day,
To the last syllable of recorded time;
And all our yesterdays have lighted fools
The way to dusty death. Out, out, brief candle!
Life's but a walking shadow, a poor player,
That struts and frets his hour upon the stage,
And then is heard no more. It is a tale
Told by an idiot, full of sound and fury,
Signifying nothing.
