2010-07-27
Explanation
This comic is titled "The Quality of Dr. Chaffin's Science Analogies Diminished Precipitously After His Tenure." It shows a bald, bespectacled professor standing in front of a chalkboard telling his class: "Think of a star as like my penis." The students stare in stunned silence, with one managing only a "So..." The professor then leans in with exaggerated intensity and says: "Huge."
The humor comes from the absurd inappropriateness of a tenured professor using such a crude analogy in a classroom setting. The title sets up the joke by explaining that Dr. Chaffin's analogies got worse after he received tenure -- a pointed commentary on how tenure (which grants job security that makes it nearly impossible to be fired) can sometimes lead professors to become lazy, eccentric, or inappropriate in their teaching, since they no longer have career consequences to worry about.
The votey panel continues the joke with Dr. Chaffin adding: "And magnetic!" -- doubling down on the inappropriate comparison while also being (arguably) scientifically accurate, since stars do have magnetic fields. This makes it even funnier because there is a kernel of scientific truth buried in the deeply unprofessional analogy.