Making a comet

My parents were always up on the latest astronomical happenings, so I saw lots of comets as I was growing up---I still remember getting out of the car by Utah Lake in the cold and dark of night, peering up at the sky with binoculars too big for my face, trying to see Halley's Comet. (I never did get a very good look at it. And it isn't going to come around again till I'm 82!) My brothers and I were marched outside night after night to follow the progress of Comets Hale-Bopp and Hyakutake as well. So I have a soft spot in my heart for comets.

We found several tutorials online for how to make your own "comet." Any day we get to use dry ice is a good day, so we gave it a try. It was fun to see the comet sublimating into the air and making icy trails as the heat of the hair dryer hit it!

This one didn't hold together very well. Perhaps our dry ice wasn't old enough (we didn't keep it overnight, as the instructions suggest). Still, we could observe pitting and sublimation at work.

This one was better. Here, we observe what happens when it's hit with "Solar wind"