Mon 10 Mar, 2014 08:12 pm - So Brandon, Ros says space is expanding, implying that the motion of the stars is not related. This raises the question of how do we know, if it is not by viewing the motion of the light emitting... (view)
Mon 10 Mar, 2014 07:30 pm - rosbourne,
Surely the expansion of the universe involves movement and hence velocity. How can something expand and not have relative motion, one side to the other?
Or are you saying that... (view)
Mon 10 Mar, 2014 07:10 pm - Dale,
Sorry to be so long in replying. I am new to this forum and I thought I would receive an email when my topic received posts.
So now having read all the posts (I'm impressed with the... (view)
Tue 4 Mar, 2014 03:34 am - Special relativity states the speed of light is the same for all observers. But astronomers talk of the doppler effect (ie blue shift) to determine relative speed between us on earth and a distant... (view)