What Color is the Sky on Mars?
I have no idea. There’s been something of a flap, because the early pictures showed it as bright pink, while anyone combining raw images from filters in Photoshop got blue. Don’t laugh, because Photoshop’s channels do a perfectly adequate job if you know what you’re doing. Now, elementary school science class tells us that blue is a shorter wavelength and scatters more, and that’s why the sky is blue. Presumably, the same laws of physics apply on Mars, meaning the sky should be blue. But the sky turns bright red every year around here, when we have our fires. There are also the many interesting shades of purple caused by L.A.’s quickly returning smog. (Thank you, SUV makers.) The NASA line about dust causing a pink sky is credible. The Martian atmosphere, such that it is, was very dusty around the time of landing. I went to the data. That’s what one does. Thought it would be a fun exercise to combine some raw Pancam images taken through the appropriate filters (L4-6). Now, I’ve been re
