Does anyone know? The sun is an average star and our solar system is located about 27,000 light years from the center of our galaxy. (We’re a tract house in the far suburbs, so to speak.) There are an estimated total of more than 200 billion stars in our galaxy and we are finding that more and more of them have planets. But interstellar distances are well, astronomical, and perhaps noticing us would be like finding a needle in a haystack.
But we have been pretty actively proclaiming our existence to the galaxy for about a hundred years, because by 1902 Guglielmo Marconi was sending and receiving Morse code by radio and ever since we have been sending out an ever-increasing stream of electromagnetic radiation. Of course, at first it was just a dribble, but now it is a constant barrage of electromagnetic signals. It is interesting to think of our solar system, which is about 11 light hours in diameter, surrounded by a cloud of electromagnetic noise about 100 light years in diameter. (A light year is the distance light or any electromagnetic radiation travels in a year, and we’ve been doing this for 100 years. A light year is six trillion miles — a number even bigger than a federal bailout.)
Our galaxy is a big place: 100,000 light years in diameter. Are there any stars within 100 light years of us? As a matter of fact, there are hundreds. The closest one is Alpha Centauri, about 3.5 light years away. Even mighty Sirius, the brightest star in the sky, is only 8 1/2 light years distant. So any aliens in the Sirius system who are advanced enough to have sensitive radio receivers know we are here.
So, why haven’t we heard from anyone? Well, maybe no one is there. (I don’t believe that. There may be no one within 100 light years of us, but surely, among 200 billion stars, there are myriad civilizations.) Possibly someone’s out there but they aren’t listening for us. Maybe they can’t detect our signals or don’t recognize them as signs of intelligence. (Suppose, for instance, they picked up a TV report from one of our political conventions. Would they think that came from an intelligent civilization?) A third possibility is that they’re transmitting for all they’re worth and we can’t detect their signals.
Even with Sirius, a very close star, we will never be able to carry on a conversation, when it takes 17 years to get a response. How many centuries would it take just to learn each other’s language? But imagine we have overcome that hurdle and are anxious to take advantage of the Sirians’ advanced technology. We might ask about their principal source of energy. And they might reply: “Oh, we use the light from our sun, which we convert by magnetohydrodynamics into other forms of energy. But, hey, we really enjoyed your new movie, ‘Terminator 2: Judgment Day.’ Tell us - is John Connor now your president?”
Willis Cook is a retired electrical engineer who was born in New Orleans and grew up in the Mississippi Delta. He lives on Varner Road in Franklin County.
For all of the editorials and columns, see the Jan. 7 issue of The Commerce News.
