SciShow's Hank Green gets schooled by Bad Astronomy's Phil Plait (who, he tells Hank, has been advocating for science "Since you were a fetus") on measuring the distance of stars. Leave it to Plait to provide an engaging as well as informative offering.
The video is for “School of YouTube Week,” in which YouTube teams with Comic Relief to ask popular YouTube channels to focus on education and asks viewers to donate to education funds for children in impoverished areas worldwide. Via Laughing Squid.