I brought my twin boys with me for my television appearance this week. They are really interested in the solar system so we’ve been learning about the different planets and their moons. Neptune’s moon, Triton, has nitrogen in it’s clouds in gas form, rivers of liquid nitrogen and nitrogen snow in solid form. It’s similar to water on Earth, but liquid nitrogen is very, very cold – 320 degrees below zero. We demonstrated the effect of liquid nitrogen clouds. Combined with hot water, liquid nitrogen creates clouds of water vapor. This was the biggest cloud we’ve ever made. It filled the television studio and rolled around the expensive HD cameras. Good thing they have insurance.