Intergalactic travel – science or fiction?

I doubt any of you have failed to read a book or watch a movie that has dabbled with the fictional account of travel to other worlds. Specifically, somewhere within our galaxy; perchance a planet somewhat like ours, orbiting some distant star. But what if you wanted to know if there was even the remotest sliver of possibility in these accounts? I have recently tried to convince myself of the possibility, only to find that the hurdles required to accomplish such a feat in anything but fictional accounts are astronomical indeed.

Just to put this in perspective. Lets take the nearest star outside of our sun as our galactic destination. That would be Alpha Centauri. A favorite of sci-fi authors precisely because of its nearness. How near is it? Well, if you had a nicely paved road, and obeyed typical freeway speed limits, it would take you just under a billion years to get there. Ok, we know we all speed a little. Half a billion. I still think you will need to stop here and there to stretch your legs along the road. Silly me – who drives a car to a star? Let’s instead take a fancy space shuttle. At nearly 18,000 mph, we can reduce our travel time to about a million years! I think we might get hungry along the way. Too bad there are no small towns or gas stations where we could stop and refill.

So if we are not going to take the shuttle, what could we take? We could try other options, like light sails, ionic or nuclear propulsion systems. But, we will instead cut to the chase. Let’s assume you have the most advanced propulsion system that can theoretically exist. An antimatter drive! Yup, antimatter is real. Not much of it yet, but it can be made, even if it is but one atom at a time. Let’s further assume you want to get there and return to tell of your tale to someone you know. Forty years sounds about right. Twenty years out, twenty back. That, in case you were doing the math, is 1/5th of the speed of light. On average! How much antimatter would it take to do this? Depends greatly on how big a ship you intend on taking for a spin. But roughly speaking, maybe a ton of antimatter would do it. So if someone handed me a ton of antimatter, could it be done? Not today. Remember, I still have to control the antimatter-matter annihilations that create my propulsive energy. And trust me, to get me there and back in the required time, we have to burn it hot. Real hot. Too hot for any known element to withstand. And then there is the unpleasantness of radiation, and the Kuiper belt, and the Oort cloud to get past; and all this just within our own puny solar system. Not to mention having to eat, drink, breathe and keep warm for all those years.

I guess what I am saying is that you should not hold your breath for any imminent human travels beyond our backyard. A shame. I so enjoyed holding on to the illusion of possibility!