Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Age versus Size of Universe
Name: Eric
Status: other
Grade: other
Location: NV
Country: N/A
Date: N/A

If we are able to see galaxies that are 12 billion light years away in both directions, how long did it take for those objects to get that far apart from each other? Surely they cannot be moving away from each other (or us) at the speed of light! Even if the separating speed averaged one-half the speed of light, they must have taken 24 billion years just to get to where they were, as we see them, 12 billion years ago. Now add the 12 billion years that the light took to get to us so we can observe them, and that makes at least 36 billion years, doesn't it?


I do not think it works that way. We are not in the middle of the Universe,

and the farthest galaxies measure in at about 13 billion light years.


David Levy


I think you may be working on the misinterpretation of the concept of the Big Bang and the corollary idea that the universe is expanding with the idea that galaxies that are currently moving away from us have been doing so since the Big Bang.

Imagine for the moment that the Big Bang created a universe that is practically as large as it is now in the first few seconds of the Big Bang event. Then imagine that the universe continued to expand -although nowhere near as fast as it did in the first few seconds of the Big Bang event - due either to the residual effect of the Big Bang or, as some are beginning to theorize, the natural action of vacuum, then any galaxy that is formed after the few seconds of universe development will be formed at a certain distance away from us and will move away from us at the rate relative to its distance from us and as a function of the current rate of expansion of the universe.

Greg (Roberto Gregorius)

Click here to return to the Astronomy Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (, or at Argonne's Educational Programs

Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory