A few weeks ago, the family and I piled into the Suburban and ventured down to Southern Arizona for a long weekend vacation. One of the stops we made was Kitt Peak, home to an array of telescopes. The plan was to participate in the night viewing session, but, alas, the impending monsoon rains put an end to that idea. So we amused ourselves by checking out all the various scopes on the mountain, even it was during daylight. They were very impressive, indeed.
The telescope that got my brain churning was the solar scope. It was an awesome piece of technology, but the visual aid in the lobby of the adjoining building was what captured my imagination. It showed a side by side comparison of the various bodies that make up our solar system, with Earth being dwarfed by Jupiter, and Jupiter, in turn, being tiny in comparison to our sun. It was like placing a bowling ball next to a group of marbles. (Here's a close approximation.) The next panel showed our sun as being tiny compared to Sirius and Arcturus. Finally, the last panel showed how puny Arcturus was when placed next to Antares and Betelgeuse.
It was quite breathtaking to see just how our own little blue orb fit into the grand scheme of the objects speeding through the expanse of space. Seeing God's creation not just on our own world but out in the rest of the universe is awe-inspiring and humbling.
It got me to thinking about whether or not some other planet like our own was out there, with some chubby kid pondering his own world's place in the order of things. So, I did what any self-respecting geek would do. I got out my calculator.
As an aside: Those who know me know that I am a Bible-believing, hard core Christian. God is powerful and great and created all that I was looking at and thinking about at Kitt Peak. But, unlike some Christians (and much like many others) I also believe that God can create things the was that he sees fit, even if he didn't explain it all to us in the Bible. For example, He very well could have created the entire universe, earth, sun, moon, sky, plants, animals, and human race in six literal, 24-hour days. But the evidence that he left behind for us to find is that he took much longer. Like 15 billion years longer. That doesn't mean that the Bible is wrong or that God didn't create the universe. It just means that the six days in Genesis does not mean six 24-hour days.
Back to the calculator. Current scientific thinking is that the Earth is roughly 5 billion years old and that the universe was around for 10 billion years prior to that. If we assume (based on what? Just the fact that I like to keep numbers round and easy to work with) the universe needed 5 billion years before any stars and planets suitable for intelligent life could develop, that means that there could have been intelligent life for 5 billion years prior to our own planet even forming. Take that 5 billion and add it to the age of Earth, and you can figure that intelligent beings have had 10 billion years to explore.
Now, humans have gone from banging rocks together and living in caves to exploring space in roughly 10,000 years. Let's assume it takes another 15,000 years for us to unlock the key to deep space exploration. And let's also assume that it takes 50,000 years more to find another habitable planet. That would (according to the calculator) mean that in the span of 100,000 years, an intelligent creature could go from banging rocks to "Take me to your leader."
Compared to 10 billion years, 100,000 is a very short period of time. It means that there has been the potential to see 100,000 new civilizations rise up, explore deep space, and disappear and have no two ever exist at the same time. It also means that just in the time that our own planet has been around, 50,000 such civilizations could have risen, explored, and died.
These numbers raised three possibilities to me: The first is that our universe is so old and our time in it so short, it is quite possible that other intelligent beings have existed somewhere out there but may have died 2 billion years ago and we'd never be able to communicate with them. Just because there are other places to live in space doesn't mean that intelligent creatures live there right now.
The second, more compelling thought I took away from the calculator is that if there had been all these other intelligent beings out there, living, working, and exploring in space (even if they all died eons ago), you'd think that by now we see some of their junk or other signs of them - radio waves, electromagnetic signals, anything that would denote an intelligence. We haven't seen anything.
The third possibility is that the universe is teeming with intelligent life, much like an ocean or jungle. But the distance between our own solar system and theirs is so vast and the rules of physics so inflexible that it is simply impossible to cross the distance between us.
So, for all intents and purposes, we are most likely alone in the universe - at least our little corner of it. And that's OK with me. It would be just my luck that some intergalactic vessel would get stranded on this planet and that their ship was fueled by Ho Hos, and they would need the world's supply of my favorite snack to return home. If that were the case, I would tell ET to phone his world's equivalent of AAA for a tow truck because he's not getting any dessert from the Fat Kid!
