Dirt was the topic at this month’s After Dark event at the Exploratotrium. All kinds of dirt. The sun began to set few minutes before Paul Doherty’s lecture at on Extraterrestrial Dirt. While we all rang bells, Paul used his finger to simulate the horizon during the sunset, slowly raising it to obscure the image of the sun in the slide he was projecting.
However, that was neither a sunset nor the horizon on the planet earth. We were looking at a sunrise on Mars. One interesting thing we learned was that sunrises and sunsets on Mars turn the sky blue- the opposite of the fiery orange that is the normal color of the sky the rest of the day.
Besides learning about the color of the sky on Mars, we got to touch a speck of the very expensive dirt from the surface of the planet that was glued to the head of a pin.