The nearest star to us is actually a red dwarf in a triple star system, with two stars larger than our sun, Alpha and Beta Centauri. The red dwarf is depicted by the red circle in the photograph. To learn more about this fascinating neighbor system, follow this link: https://en.wikipedia.org/wiki/Alpha_Centauri
I was watching a show about the asteroid belt on The Science Channel, when it suddenly occurred to me that reaching the nearest star: ‘Proxima Centauri’ wouldn’t be so difficult as it appears! The Asteroid belt starts approx. 300 million miles from here; just past the farthest point in Mars’s orbit.
Using space rocks for fuel
This is Ceres. It is the largest asteroid in the asteroid belt, with a diameter of 600 miles; more like a dwarf planet than an asteroid! An asteroid half this size would probably contain 25% water; that’s a hundred times all the fresh water on Earth! We’ve long known how to separate hydrogen from oxygen in water.
The oxygen would be useful for breathing. Some water we would drink, and some would be used as an outer skin for the star ship, to protect us from radiation. The hydrogen would be our fuel… But we’d have to shoot something deep into the asteroid to retrieve the water. A star ship making this kind of journey would have to be enormous, and rotate, to simulate earth like conditions, and artificial gravity. It will take 42 years to get where we’re going, so passengers should be young if they hope to see the place…
At the 3 billion mile mark, we have another set of rocks 250 times as large as the asteroid belt, just loaded with more fueling stations! ‘The Keiper Belt.’ At the 6 trillion mile mark, we run into: ‘The Oort cloud’, which I suspect is just more rocks to fuel up with; but they’re s0 far away, it just looks like a cloud. So we can fuel up here too!
At the other end, we have a system with two large stars, and a dwarf star. It’s ‘Oort Cloud’ probably stretches out 2 light years from the central system; that’s 3 light years worth of fillings stations then, which leaves only one light year between the two systems, which might have wandering rocks anyway. Besides, a city sized ship could process enough fusion power to take you one light year, at one tenth the speed of light; it would pass the moon in eight seconds! It would reach The Keiper belt in 30 hours! That’s incredibly fast!
The two large stars Alpha and Beta Centauri shed far too much radiation, and tug too much upon each other to harbor planets in any reasonable orbits at all without flinging them out into space, or gobbling them up in a gravitational tug of war! Pictured above is Proxima Centauri, owning at least three planets that we know of, and assorted moons; far enough away from the influence of the other two stars! And one of them is in ‘The Goldilocks Zone’ where life may have evolved! If not? What The Heck? We gave it a shot! LOL!