Cosmic scales

Ever since I was a little kid, I have enjoyed astronomy. Part of the reason has been the mind-boggling scale of our universe. I thought about that the other day and looked up in reference books various ways to understand the size of our solar system and the universe in which it is situated. I thought you might like to read some of these.

Let's start with the solar system. If the sun was represented by a yellow beach ball with a 2-foot diameter, the earth would be the size of a pea 215 feet away and Jupiter would be the size of a large orange 1,056 feet away. Or consider this other scale: if we represent the sun by a large orange, the earth would be a sesame seed about 49 feet away and Pluto, a grain of millet, would be over 3,400 feet away. According to this scale, the nearest star to the sun, Alpha Centauri, would be nearly 2,500 miles away. Now, let's consider cosmic distances. If you could drive to the sun at 55 mph, it would take 193 years to get there. If you wanted to get to Alpha Centauri, you take 52 million years at the same speed. Here are other ways to think about sizes. The sun weighs as much as 300,000 planets like Earth. Over 1 million earths would fit inside the sun. The moon's entire orbit around the Earth could fit inside the sun.

All right, much of that was mind-boggling, but it gets crazier when you consider the Milky Way galaxy in which our solar system is found. If the diameter of our solar system was scaled to 1 inch, then our galaxy's diameter would be about 100,000 miles. If our entire solar system could fit into a coffee cup, our Milky Way galaxy would be the size of North America. If you took an Apollo spacecraft to Alpha Centauri, the nearest star, it would take 850,000 years to get there. Or, think about this. If our sun was represented by a basketball in New York City, the next star would be a basketball about 5000 miles away.

For some people, the message in the above statistics is that we are insignificant. We live on a nondescript planet and circle an average sun near the edge of an typical galaxy. But discoveries in the last 10-20 years have shown that this is not the true picture after all. So much has to happen exactly right to produce life that it appears to be extremely rare. In fact, Paul Davies, who is a well-known secular physicist and professor, says he believes we may be the only intelligence in the entire universe. So, the question becomes very simple -- are we the product of chance or intelligence? To get things so exact both on the cosmic scale and down to our cellular makeup (consider DNA, for example), it requires the intervention of an intelligent agent. I think I know who that is.