At the bottom of this entry, I give the Weekly Pondering 1 assignment, for those of you in ASTR 1/2. There is also a link to submit your assignment.

It could be argued that scientific revolutions tend to be led by people who ask novel and radical questions. Max Planck, for example, asked what one would find if one assumed that light is emitted in packets, a bit like dollars and cents; he derived a model of light emission based on that hypothesis. This concept fundamentally deviated from the understanding of light that was ubiquitous at the time. Even Max Planck had not grasped the meaning of this idea; it was Albert Einstein who, several years later, gave a physical interpretation. This served as the basis for what we refer to today as the quantum revolution. No one would have paid attention to Max Planck's idea, except for the fact that the common (during the 19th century) conception of light emission had utterly failed to explain the data for decades. If one studies the Sun, for example, one will find that very little radiation is emitted with small wavelengths, the amount of radiation emitted reaches a peak around visible and ultraviolet light, and then the amount emitted falls off close to zero for very large wavelengths. Max Planck's model easily explained this observation--unlike the physics of the 19th century, which had failed quite dramatically to explain it.

This aspect of science often gets lost in the classroom, in my view. Science is frequently presented as a series of facts that students have to memorize, and, even though there are often application problems given in classrooms, this might give the impression that scientific truths come from books. In reality, we make testable hypotheses, often arising from unique questions that few people would ask, which we then compare to experiment and observation.