Some basic ideas about physics and astronomy remain so mysterious, and their explanations so flexible, they may lead some to question whether they should be called "hard sciences."
In historical sciences, observable phenomena are often used as indicators of past phenomena. Some recent examples show how these can mislead researchers.
Physics is supposed to be the king of “hard science” because of its precise mathematics, predictability and falsifiability. When transferred off our planet, however, it seems speculation is the order of the day.