"redbelly" wrote in message
oups.com...
md wrote:

When we measure the red-shift of a distant
object, how can we conclude that it moves
away from us? It might also be that it is not
moving away, but it is very heavy instead?

We also observe that the red shift increases
with distance. If it's a gravitational effect, it
would mean that objects tend to be more
massive the further away they are from our
galaxy. That's a pretty silly idea,

why is that a "silly" idea?? you mean "different"?