So here’s my latest round of navel-gazing, which is deeper than usual (for reasons undiscovered by me):
1. I have been thinking a lot lately about life on other planets. That is, whether or not it’s useful to us to discover it exists. Okay, so on a “spiritual” level (for lack of a better term), sure it’s useful. It helps us to know we’re not alone in the universe. It possibly also helps us to know that maybe somebody has gone through similar experiences as we have, as a species.
However, how practical is this knowledge? What I’m basing all this debate on is this – the speed of light. Ultimately, light, though very fast, travels at finite speeds. An object that is one million light years away is still one million light years away. Therefore, were there to be a civilization on a planet, we’d be seeing one million years into that planet’s past. For example, a civilization one million light years away that’s just receiving light from our planet, would see our history before human beings ever existed, provided they could see Earth in such detail (who knows? maybe they’ve figured that out). And then if we saw evidence of a civilization on a planet one million light years away, who’s to say that it’s still there, or that the planet even exists any more? I mentioned this to my husband, who mentioned faster-than-light travel, which brought on an additional discussion of relativity and its limitations given our current knowledge of the laws of physics, and I’m still left thinking about the what ifs.
Apparently this is something that SETI researchers struggle with on a regular basis.
(More to follow tomorrow, with Part 2.)