Quote:
Originally Posted by skyline5k
I'm grabbing my info from Wikipedia. Assuming Fomalhaut is about 25 light years away, is it also safe to assume that we're looking at Fomalhaut 25 years ago? |
That's one way to view it. It makes language difficult though. Many just don't let the lightspeed get in the way and speak of events at great distances just as they do ones at nearby distances, saying, for instance, they occur when the signal arrives.
As the Bad Astronomer said, in
BA Blog: Mi Cas A es su Cas A (about an event happening 10000 lightyears away, recorded in 1680):
Quote:
|
Footnote: Yes, I know– some of you will think that it didn’t blow up in 1680, that’s just when the light reached us, and it really blew up 10,000 years ago. I disagree. We cannot say anything about that event until the light reaches us, and in a real sense that event has not happened until the light reaches us. Time flows like light, I sometimes say, meaning that the event itself happens when the light reaches us. So it is acceptable to say that the explosion actually happened in 1680.
|