In addition to these methods, we also have an excellent understanding of how stars work. Our models of stellar structure are excellent predictors of the properties and evolution of stars. As it turns out, the mass of a star determines its life history from day 1, for all times thereafter, not only when the star is on the Main Sequence. So actually, the position of a star on the H-R diagram is a good indicator of its mass, regardless of whether it's on the Main Sequence or not.
Have you ever observed nuclear fusion? Have you ever seen an atom? Ever noticed that Quantum Mechanics is based on probabilities and assumptions to prevent the model from falling apart? We know absolutely nothing about stars. We have never observed a single one beyond wavelength. We know even less about the "atom"... after 100s of years chemists have failed in their original goal: making gold, and they have failed to describe the nature of matter as well!
For low cost observations of nuclear fusion (non government), try General Fusion.
http://www.generalfusion.com/files/evidence.pdfFor observations of a star beyond "one wavelength", try here:
http://www.theflatearthsociety.org/forum/index.php?topic=21793.0I will also be happy to restart the Solar Neutrino thread, starting with plenty of relevant hardware information.
Next, "We know even less about the "atom"... ", except that we know it doesn't look like proton-neutron pudding. We also know that we can smash atoms together and make pretty pictures like this:
http://en.wikipedia.org/wiki/Particle_physicsI would say that is something.