Friday, February 4, 2011
Why Should We Go to Space?
Every year, as the United States has to draw up its budget, there are lots of considerations. How much do we spend on defense? How much can we afford to take care of the poor, the elderly, the children? How much do we send abroad for humanitarian purposes? And how much do we invest in education, and technological advancements here at home? Each of these are very important, but when money is tight, we have to make some difficult decisions. We have to get our priorities in order, and the composition of the government determines those priorities, sometimes but not always along party lines.
When it comes to making cuts, space exploration sometimes finds itself on shaky ground. It can feel like a luxury item, like that cable sports package we like but don't really need. Looking at the billions of dollars spent on manned space flight or space telescopes, for instance, it's easy to wonder how many children that might feed, or how many teachers that could pay (but of course, it's an equally valid question to ask how many fighter jets and warheads we could stand to do without). No expenditure exists in a vacuum, though, so while we can easily imagine all the good that an extra 10 billion dollars might do for any single program, we have lots of commitments and we have to figure out how to spread the money around to cover all our bases.
Our ventures in space began with a decidedly defensive purpose. When the Soviet Union launched Sputnik in 1957, it became clear that we were vulnerable to an unprecedented threat: intercontinental ballistic missiles. As was typical of the Cold War, we set about the task of demonstrating our technological prowess. It was a matter of national security, after all; the best way to deter the Russians from destroying us with ICBMs was to make sure everyone knew we could do the same thing to them. But as a lovely side effect of that scary time, the United States began a preliminary reconnaissance of the solar system. In a breathtaking achievement, the US landed a man on the Moon just 12 years after the first satellite was launched, and only 66 years after the Wright Brothers' first powered flight. Since the beginning of the space age, we Earthlings have sent robotic emissaries to all of the major planets; investigated the myriad moons of the outer solar system; landed robotic spacecraft on Mars, Venus, and Saturn's moon Titan, with a few rovers exploring the Martian landscape; built an enormous space station in Earth orbit; connected the world through a dazzling array of communications satellites; and stared into the vast depths of space, peering 13 billion years into our remote past, and accumulating data that is impossible to collect from Earth's surface.
We are so incredibly fortunate to live in this age of great discovery. The human species has spent its entire modern existence -- many thousands of years -- looking up at the stars and wondering what they are. But it's only in the last 2 or 3 percent of that history that we have been able to work out some of the answers.
Our ancestors of antiquity cataloged the skies, investigating the structure and mechanics of the universe as it was then known, studying the motions of the planets and drawing some remarkable conclusions. In just the last 500 years or so, we have made the most astonishing breakthroughs in our understanding of the cosmos: discovering at last the heliocentric structure of the solar system, the elliptical orbits of the planets, the nature of gravity, the existence of new planets, the galaxies, the extraordinary properties of light, the theory of relativity, and the Big Bang. All of these spectacular discoveries were made by humans before we ever had a chance to go up in the sky and take a closer look.
This is our heritage. The thousands of generations before us lived and died with only a vague understanding of the immeasurable universe beyond our atmosphere, but their collective contributions have brought us to this pivotal moment. It's up to us now to make our contribution. If we do not, the next generation will have to do it for us, but we owe it to them to go as far as we can, so that they can go even farther.
As inspiring as astronomy can be, though, it will always be tempered by terrestrial concerns. But for the practical mind, there are tangible reasons why we must continue our work in space. We know that the universe is not static. It is a dynamic, perilous and indifferent place, and our survival depends on how well we understand our cosmic neighborhood. Earth is the only planet so far as we know where we humans can reside comfortably, but there is no guarantee that our home world will always be perfectly hospitable, and we do not yet possess the technology to escape in the event of catastrophe. It's not very likely that we'll see something like it in our lifetimes, but there is always the chance that a yet-undiscovered asteroid or comet could slam into us and end humanity's brief reign on the Earth. For the first time, we have the capacity to avoid such a calamity, but we should take appropriate steps now. Meanwhile, we know that our mighty Sun is capable of doing tremendous damage to our technological infrastructure, so it's worth continued study. Global climate change remains a serious threat, and satellites have provided us an abundance of meteorological data. At the same time, our investigations of the Martian and Venusian climates have provided real examples of what Earth might look like with a runaway greenhouse effect, or without an ozone layer.
But history tells us something else about the value of science. In many instances, scientific discoveries have had applications far beyond the imaginations of the people living at the time. When magnetism was first investigated in Ancient Greece, the navigational compass was still 1500 years in the future, and certainly no one could have imagined something like magnetic tape, which was critical to audio, video, and data recording for most of the 20th century. The importance of genetics and its promise for medicine could not have been fully grasped at the time Gregor Mendel was working with his peas. When Benjamin Franklin performed his famous kite experiment, it's unlikely that anyone could have predicted something like the television or the internet. And the pioneers of chemistry in the early 1800s could not possibly have suspected the awesome power contained within the atom.
When we look at the countless discoveries of the last few thousand years, time and time again we see a pattern of marvelous and unexpected scientific breakthroughs which could not have been possible without the work of those who came before. And such is the case today. Sometimes we just don't know what we'll find around the next corner, and we can't possibly know what that discovery will mean for the future. Scientific studies can sometimes appear to have little application for everyday society, but it's impossible to know when the next unexpected, world-changing discovery might come. We just have to keep working.
In any case, it would be a mistake to minimize space exploration's visceral appeal. There remains great enthusiasm for the latest scientific discoveries, whether we're talking about finding new exoplanets or a tantalizing astrobiological discovery. The general public is enamored with the future, and science is the means to get there. But more than that, exploration is a part of us. We have always been explorers, and when the Earth was finally mapped in its entirety, we craved a new mission. The next frontier is space, and it holds enough mystery to occupy thousands of generations to come. So far, space exploration is too expensive for most private interests, so it's up to the government to do it. But in time we can expect more private involvement in space. We are seeing the start of it now.
Space travel is the crowning achievement of human technology. Just as funding for the arts can be difficult to justify in concrete terms, it can be hard to quantify the value of our work in space. We cannot put a price tag on the expansion of human knowledge. But our space endeavors represent the pinnacle of human potential. At long last, we are spacefarers. It is our future, and we would be well advised to embrace it.