On 30/03/2017 19:39, Bill Wright wrote:
I'm hopeless at maths, but I'm trying to get something across to an
intelligent child. So, if the distance from here to London (250km) is
represented by the thickness of a hair (0.2mm) how far is a light year?
It doesn't have to be a hair; it could be anything familiar and small.

It's 2.5 million light years to the Andromeda Galaxy; that's what we're
discussing.

Help!

Bill

If here to London becomes here to Andromeda, then the human hair becomes
2km thick.

Jim