Tuesday, January 11, 2011
The Long Run
My career plans are a bit unorthodox, so I think it might be a good idea for me to take a moment to explain what exactly it is I want to do after I get that magic piece of paper four months from now enabling me to legitimately call myself a rocket scientist. I've thought about this a lot, and think it's important, but I don't often see people talk about the kind of future I want to work towards.
Compared to things on a human scale, the universe is pretty old. Barring illness, malice, or accident, a person can expect to live about a hundred years, give or take (mostly take) a score, and that's about a hundred-millionth the age of the universe. I've gotten pretty good at dealing with numbers over the years, but I can't even begin to comprehend on a raw, visceral level a time that so completely dwarfs all the time a human life can span. It's just, big, mega-big, I say to myself, with a tremble of awe.
Knowing this, saying that the universe is in its infancy sounds laughable. But for many of the current residents of the cosmos, much more lies ahead than behind. About three-fourths of the stars shining in the Milky Way right now are M class red dwarfs, the dimmest, coolest, littlest stars burning hydrogen into helium. Each of these stars will keep shining for up to a few trillion years from now, meaning many of them aren't even 1% through their lives. Long after the oceans of Earth have boiled away and the Sun has collapsed and cooled into a dim white dwarf, the universe will shine on, a bit dimmer, a bit redder, but steady across the ages. The universe is not old. It will be a child universe until every bright yellow star like the Sun has burned out and shriveled away.
Like the universe, humanity is in its infancy, on the edge of some new age. Humans in their present form have been around for about a hundred thousand years, again a dizzyingly long time from a single person's perspective. I often wonder what it would be like to be one of those people, long before the library, the written word, before even agriculture. They were about as smart as us, as curious, as clever, as compelled to awe and understanding and the emotions of people everywhere. It must have seemed so impossible to ever understand how anything worked when so much seemed downright inscrutable and arbitrary. But they kept at it, and though it took millennium after millennium of discouraging progress, the why and the how of crop growth, writing, math, civilization, astronomy, physics, and biology started to come together. We are outrageously privileged to live in the time we do, blessed with a thousand centuries' worth of labor toward understanding the world and enabling a human presence in it without asking for it and without deserving it.
Think for a moment about what those thousand centuries are compared to the youthful age of the universe. Nothing more than a few hours in a lifetime. Clearly, there's a lot of room for progress.
I don't know what Earth's capacity for supporting human life is, but I think it's reasonable to say that we're within an order of magnitude of it already (at least with foreseeable technology). If we are to continue growing, expanding, evolving as a civilization we need to look outward. By happy coincidence, humans finished fully exploring Earth at almost exactly the same time that we first became capable of exploring beyond. Human exploration and ultimately human settlement of space is limited by economics, not physics. The energy costs of flying a person around the world are about the same as the energy costs of flying a person to low Earth orbit. Once there, as Heinlein elegantly put it, you're halfway to anywhere else in the solar system, by energy at least. Clearly there's a way to settle a new frontier beyond Earth so that it is a boost, not a drain, to our global economy. We just haven't hit on the right utilization of technology yet.
This is what it will take to enable a long-term positive future for cvilization development. We can either develop the technology to affordably travel to and from low Earth orbit and live off the local resources, or civilization can remain confined to Earth and it's truncated timeline. Civilization can continue to climb and yearn and keep on developing on the timescale on which the stars live, or it can stagnate and we can all live as steampunk cavemen for a billion years. I'd rather climb.
So what do you do on a day-to-day basis to help create this future for humanity? I'm not exactly sure, but I think, and I hope, that what I'm doing right now is a good start.