How Do Scientists Know It's Space Expanding Not Galaxies Moving?

[Alex K]

Wow, I only had to read this three times to understand it. I think I'll have a clearer understanding of what you're saying if I understood redshifting mathematically. I'm thinking of it as a color. The color may fluctuate in intensity because of varying circumstances, but I still don't know enough about it to think of it as having sums and differences.

Thanks Brian, your answer may be right, but I still think my question will help me understand what Alex said. He's a teacher, and a damn ggood one at that. In the couple years he's been working with me, he never once suggested that I couldn't understand something and I've always been able to zero in on the part of his answers that will hep me understand what he says. His patience is his gift.

I teach calculus to future child care workers with approx. 0 interest in maths. For that you either have infinite patience or you'll be very unhappy