Back to Home

Blackholes2 Forum Message

Forums: Atm · Astrophotography · Blackholes · Blackholes2 · CCD · Celestron · Domes · Education
Eyepieces · Meade · Misc. · God and Science · SETI · Software · UFO · XEphem
RSS Button

Home | Discussion Forums | Blackholes II | Post
Login

Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...
The Space and Astronomy Agora
That's Just Rhetoric

Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response To
Posted by Rich on December 20, 2000 21:41:43 UTC

We do not see the Andromeda Galaxy as it was 2 million years ago. We see the light it made 2 million years ago. The light we see is the light that is visual to us as of now.
Suppose you are on Earth and the Andromeda galaxy hasn't formed yet. You look into the sky and see nothing. Then the galaxy forms and finally two million years later, you see the galaxy's first light that has reached Earth. You never see the galaxy itself though. You just see the part that has reached us. And when the galaxy dies, for two million years you won't know it because the info hasn't arrived yet. It has happened, but you don't know it yet.
A parallel? You and I are in a room. You are going to take a seat. I play a prank and pull the seat away from you. You then sit down, unknowingly, and fall to the ground. When you hit the ground, you now know that the chair moved. But that doesn't mean that you are seeing into the past. It just means you learned something after the fact. To you the knowledge of the chair being moved happened ten seconds after I knew the chair was moved. Your knowledge is just relative. The chair was moved at the same time to both, its just when you actually knew it that changed.

Follow Ups:

Login to Post
Additional Information
Google
 
Web www.astronomy.net
DayNightLine
About Astronomy Net | Advertise on Astronomy Net | Contact & Comments | Privacy Policy
Unless otherwise specified, web site content Copyright 1994-2024 John Huggins All Rights Reserved
Forum posts are Copyright their authors as specified in the heading above the post.
"dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET"
are trademarks of John Huggins