Death on Pluto

Today the NASA spacecraft sped past (the planet?) Pluto and made it’s closet approach at an altitude of around 12,500km. To date, nothing groundbreaking has been found out about Pluto although plenty of new information about the planet is due to be beamed back in the upcoming hour and days. However, the event reminded me of a discussion I have most years with my students when I am teaching about solids, liquids and gases and the gas laws (you will now ...