Age of a Distant Galaxy: Is It Double?

  • Thread starter Thread starter AndersHermansson
  • Start date Start date
  • Tags Tags
    Age
AI Thread Summary
The discussion centers on the interpretation of the distance of a distant galaxy, specifically questioning whether the commonly accepted distance of 12 billion light years accounts for the galaxy's movement away from us. Participants argue that since the galaxy has been moving, the actual distance should be greater than 12 billion light years. They emphasize that we are observing the galaxy as it was 12 billion years ago, not its current state. This leads to the conclusion that significant changes may have occurred since that time. The conversation highlights the complexities of measuring cosmic distances in the context of an expanding universe.
AndersHermansson
Messages
61
Reaction score
0
If the light reaching us from a distant galaxy is said to has been traveling for 12 billion years, then it is said to be 12 billion light years away. Did someone forget to consider the fact that the galaxy has been moving away from us in the meantime? The distance must be at least the double.
 
Astronomy news on Phys.org
Originally posted by AndersHermansson
If the light reaching us from a distant galaxy is said to has been traveling for 12 billion years, then it is said to be 12 billion light years away. Did someone forget to consider the fact that the galaxy has been moving away from us in the meantime? The distance must be at least the double.

That's why they always say that we are only seeing things as they were 12 billion years ago.
 


Originally posted by Mentat
That's why they always say that we are only seeing things as they were 12 billion years ago.

What Mentat said. We are seeing what the conditions are like THEN! A lot probably has changed if we were to see things locally.
 
This thread is dedicated to the beauty and awesomeness of our Universe. If you feel like it, please share video clips and photos (or nice animations) of space and objects in space in this thread. Your posts, clips and photos may by all means include scientific information; that does not make it less beautiful to me (n.b. the posts must of course comply with the PF guidelines, i.e. regarding science, only mainstream science is allowed, fringe/pseudoscience is not allowed). n.b. I start this...
Asteroid, Data - 1.2% risk of an impact on December 22, 2032. The estimated diameter is 55 m and an impact would likely release an energy of 8 megatons of TNT equivalent, although these numbers have a large uncertainty - it could also be 1 or 100 megatons. Currently the object has level 3 on the Torino scale, the second-highest ever (after Apophis) and only the third object to exceed level 1. Most likely it will miss, and if it hits then most likely it'll hit an ocean and be harmless, but...

Similar threads

Back
Top