Happy Halloween

General 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 | Misc. Topics | Post
Login

Be the first pioneers to continue the Astronomy Discussions at our new Astronomy meeting place...
The Space and Astronomy Agora
Here's Another Way Of Saying It

Forum List | Follow Ups | Post Message | Back to Thread Topics | In Response To
Posted by Nicholas on November 29, 2002 00:51:43 UTC

The light from the objects with the highest redshift that we currently see (z=6) was emitted about 15 billion years ago (roughly the age of the universe). At the time that the light we see was emitted, the universe was much smaller, so the separation between us and the object was less than 15 billion light years. As the universe expanded, however, the separation between us and the object grew. Thus, as the light traveled, it had to compensate for this extra distance created by expansion. It didn't actually reach us until the present time, 15 billion years later.

The PRESENT state of the objects we see at z=6 is unknown, though we can estimate their PRESENT distance from the expansion rate of the universe. I assume this is the number you quoted, 27 billion light years. We can't see them in their present state, so we don't know for sure how far away they are. They are outside of our "light cone", so to speak.

Hope this helps.

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 1994-2019 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