High and far

Imagine you are out one night and you see a plane flying over your head.
Someone might note that it is 10 km high. Now imagine that exactly
behind the plane is the Andromeda galaxy. No one is going to say that
the galaxy is 2.5 million light years high, one would say it is 2.5
million light years away. Conversely, for the plane no one would say it
is 10 km away if it is directly over head. So at what point does
something cease to be up and starts to be far.

Now this might seem like being only semantics, and it is. But I think
that discussing this particular point of semantics sheds light on how
people perceive space. I have my own opinion on the matter but I will
give it only after others have given their opinion, because I don't want
this thread to be about discussing my opinion. I want it to be about
seeing what are the different opinions out there.


Alain Fournier