dr. neil degrasse tyson. >>> pluto's really puny, right? ury. >> pluto is a lot punier. 1/20 the mass. of mercury. >> less than the mass of the moon. >> touchdown right there. >> that's from neil degrasse tyson's new pbs nova documentary "the pluto files." dr. tyson is the guy who killed pluto. that is, it was dr. tyson and his team at the hayden planetarium at new york city who decided ten years ago to not call pluto a planet anymore and instead classify it as part of a distant asteroid belt. instead of remembering the planets by memorizing my very excellent mother just served us nine pizzas mercury veinous earth mars jupiter saturn uranus neptune pluto. you instead have to memorize my very excellent mother just served us nachos. no more pizza. no more pluto. for being the first physicist to reclassify pluto he got hate mail from third graders who wanted to know what he had done with the planet they loved and who no one admits was the inspiration for the name of mickey's dog. turns out americans are weirdly intensely in love with pluto. it'