>The main exception is that they use the non-SI unit AU quite >a bit. Maybe you'd brand me a heretic, but I think this is a >useful unit for discussing distances of objects in relation >to Earth - it beats "so many million km from Earth."
I think 'million km' beats AU. I am familiar with metres and see them all around me but have no idea about AU. Incidentally, 'million km' is not the only SI compliant way of expressing a distance of that magnitude. However, people appear reluctant to apply the prefixes beyond kilo to metres and grams. Does anybody have any idea why that is?
