(March 7, 2014 at 5:52 pm)pocaracas Wrote:(March 7, 2014 at 4:51 pm)rsb Wrote: The big bang is just a theory, with only really 1 observable, background radiation and expansion.That's 2 observables...
And you forgot the usage of spectroscopy to determine the distance of far away stars, and also their element content.
The farther away, the oldest, the simpler the elements present in the star.
So using that logic it's possible to determine which of these lights is the oldest. I wonder which one it is?
http://apod.nasa.gov/apod/ap001127.html