Matt cools his face

So, it turns out there are some upsides to being a summer research student in a physics department. We stayed after work yesterday and played with liquid nitrogen yesterday for a few hours. It's completely harmless to humans, except for the fact that it's about 77K, or -196 degrees Celsius. (I'm not going to quote the temperature in Fahrenheit - if you're American, tough luck. You really need to start using the same standard units as the rest of the world.) Anyway, it's cold. If you stuck your hand in it for more than a few seconds it would be frozen solid and you'd be able to shatter it with a sharp blow!

In this photo, Matt is cooling his face down. Simply place your head above the nitrogen, blow into the liquid and enjoy feeling your breath come back out of the container towards you along with a lot of freshly evaporated nitrogen! Lovely cool breeze.