
As a child, I was fascinated by the planets.
I think the solar system one of those things that all children are fascinated by, like dinosaurs. At that age we are completely engrossed in learning about our world, and the thought of another world that’s not like the one we see around us is even more amazing.
Did dinosaurs really once walk the Earth huge beasts like monsters out of cartoons that seem so out-of-place in the world around us?
Are there really entire other worlds, with mountains and moons and air you can’t breathe?
As children, we are busy learning what the world really is. We have not yet closed our horizons to encompass only that which is practical, immediate, or commonplace. To children, adults’ relative indifference to staggering facts such as dinosaurs and other planets must seem strange. For how can such a big part of reality be ignored?
And yet, we do ignore it. As we grow up and become consumed with the necessities of life, with the practical and the immediate, we seem to lose our sense of wonder.
Not only do we cease to stop and look up at the blue sky of Earth, but we, for the most part, put other planets out of our minds entirely. Space exploration is no longer a popular topic of conversation for most adults. In fact, I’ve been shocked to find that many of today’s adults and youth alike consider space exploration to be downright irresponsible.
After reading one article I read detailing the new planets discovered by the Kepler telescope this year, a commenter asked “With all the problems down here, why are we still paying nerds to look at the stars?” This attitude echoes the sentiments voiced by many voters and political lobbyists: “The other planets may be pretty,” they say, “but there is nothing necessary or practical, nothing up there that is going to help solve the problems down here.”
Or is there?
There are still myriad technical barriers to space exploration by humans. The question has recently been raised at NASA as to whether a manned mission to Mars is even conscionable at our current level of technology; the risks to the astronauts are so great, and the vast distance would make emergency rescue utterly impossible. In
interplanetary travel, new dangers would be seen that never came into play when traveling to the Moon.
A human on the way to Mars would be so far outside of the Earths’ magnetic field that, without protection, their DNA would be shredded by cosmic rays.
The astronauts would be in zero gravity for a long time, without the benefit of people on the ground on Mars to help them get around until their muscles regain strength.
They would be trapped in a tin can with the same four or five other people for well over a year, isolated in potentially high-stress conditions.
The list of unprecedented challenges goes on. And yet, solutions for all of these problems are in the making.
Several methods have been proposed to protect astronauts from cosmic rays, though all are expensive and as of yet untested. Multiple systems have been designed to generate low levels of artificial gravity on a Mars spacecraft; these, again, have gone untested.
The list of proposed space travel technologies which have gone untested due to lack of funding or collective motivation is perhaps as long as the list of unprecedented challenges that an interplanetary explorer would face.
Many on Earth ask, why spare the expense? The cost is, admittedly, daunting— most estimates place the price tag of a manned mission to Mars at around $100 billion.
This is more than five times the total annual budget our government gives to NASA – meaning that the Space Program would need either a dramatic increase in funding, or to find a way to run all of its other programs such as weather satellites, far-seeking telescopes, and American participation on the International Space Station, on a tiny fraction of their previous budgets.
For comparison, the Department of Defense receives $20 billion annually solely for military satellites and rockets, and the wars in Iraq and Afghanistan to date have cost about $1 trillion—that’s ten manned missions to Mars.
On the face of it, incentive may seem lacking. Outside of Earth, Mars alone seems to possess a solid surface that we can actually land spacecraft on without them being instantly frozen, crushed, or melted. And Mars is not exactly a lush jungle of hospitality; it lacks oxygen, the shelter of a magnetic field, and liquid water to name a few basic necessities. So if this is our most hospitable neighbor, what exactly do other worlds have to offer us?
Stephen Hawking has a few ideas. The world-renowned physicist, who is most often in the headlines for making breakthroughs about black holes and the Big Bang, made global news last year for something very different.
He told the press that not only does he believe other planets in our galaxy are likely habitable to humans, he believes they host their own life, and he thinks alien invasion is a real and serious danger to humanity’s future.
Alien invasion isn’t the only threat Hawking is concerned about. In 2006, Hawking told reporters: “Sooner or later disasters such as an asteroid collision or a nuclear war could wipe us all out. But once we spread out into space and establish independent colonies, our future should be safe.”
Hawking’s ideas aren’t as far-fetched as you might think. The Milky Way Galaxy alone contains over 100 billion stars. For some perspective, the Universe itself is only about 13.7 billion years old. If stars were years, the Milky Way would be more than seven times older than the universe.
So unless the odds of life evolving are as small as 1 in 100 billion, the existence of alien life in the Milky Way is nearly a mathematical certainty. And alien life means far more for humans than just the possibility of invasion.
Life is the source of that precious gas, molecular oxygen.
On Earth, oxygen is a natural product of photosynthesis, and biochemistry suggests that the process could be very similar on other planets. Biochemistry also suggests that anywhere liquid water exists, life is very likely to evolve sooner or later. And mathematics suggests that it’s extremely likely that other worlds with liquid water and oxygen atmospheres exist in the Milky Way.
That’s a prospect to excite the child in all of us.