April 23, 2008

Waiting for the snow to disappear

This time of year is the least fun season in Tromsø. Knowing it is spring further south, makes it even more depressing to look outside and see snow everywhere. It varies from year to year when spring decides to show up. Anything from early April to early June is normal. This year it seems to become a late spring. The last weeks we've experienced 20-30 cm of snowfall on a daily basis. Luckily some of it thaws during the day, but we've gotten our share of excersize showeling snow.

One of the reasons I want a snowfree environment, is my discovery of a cool experiment in November last year. A couple of days before the winter kicked in, I learned about the micrometeorites. Dust from space fall to earth, tons of it every day. But every individual piece of stardust is too small or almost too small to see for the human eye. But with a magnification of just 20, they are easy to identify.

The meteorites we are talking about here are the iron-containing ones. When they enter the atmosphere, they melt and get a characteristic round shape which is easy to identify in a sample.

NASA and others have published lots about the topic, including photos and how-to's. The way I search for the extraterrestrial dust is the easiest one, I think. I use two plastic cups. Inside one of them I put a strong neodium magnet. The second cup I place on top of the magnet, locking it between the two cups. Then I tie strings to the cups in a triangular shape, allowing me to walk straight and hold the cups just centimeters above the ground. With this you're ready to hunt for the stardust, taking your cups for a stroll or three. The micrometeorites will be attracted to the magnet and stick to the bottom of the cups. To check if your sample contains the round beads, transfer it to a post-it note and look at it with 20x magnification or more. Good luck hunting!