What timing! I’ve been spending the last few weeks trying to help my astronomically-neophyte Sweetie grasp the idea of time traveling with stars. When we look at Barnard’s Star, we’re not seeing how it looks at this moment – we’re seeing what it looked like six years ago because that’s how long it took the light to reach us. It’s something us long-time amateurs take for granted, but it’s not an easy concept.
Last week while we were watching the CBS Evening News, a segment came on about how astronomers have discovered the oldest and most distant spiral galaxy yet – located roughly 10.7 billion light years from us.
I turned to see if Sweetie had registered the immensity of that distance, and could tell immediately by the expression on his face that it had.
“Wow! What’d he say? Like 10 billion light years away? Ten billion! But wait, we’re looking back in time. So we’re seeing how it looked 10 billion years ago, right?”
But later it occurred to me that if I had been watching the news by myself, that number would have probably just bounced off my forehead. Do you remember how blown away you were the first time a reality like that really sunk into your mind?
I guess we all get jaded – tossing around huge numbers and distances and sizes, and in the process, have forgotten the excitement of what they represent. So I always appreciate it when something happens to remind me of the vastness of it all. I mean think of it – it’s taken 10 billion years for the light from BX442 to reach us. Ten billion!
Hmm. So now I’m wondering what BX442 looks like today?…