How does knowing where you receive information from make your thoughts more valid?

Supposedly a fact can be traced back to observations and experiments to verify it. But in practice, it is used as a source of authority. For example Galileo was scolded for doing his own experiments instead of accepting the commandments of the church. In modern times, actual science gets rejected when it contradicts the consensus. Consensus says the sun is powered by fusion, which implies the inside should be hotter than the outside. A casual observation shows the reverse. So your observation is rejected and they shout insults at you until you go away.