Researchers calculate size of particles in Martian clouds of CO2 snow
In the dead of a Martian winter, clouds of snow blanket the Red Planet’s poles — but unlike our water-based snow, the particles on Mars are frozen crystals of carbon dioxide. Most of the Martian atmosphere is composed of carbon dioxide, and in the winter, the poles get so cold — cold enough to freeze alcohol — that the gas condenses, forming tiny particles of snow. Now researchers at MIT have calculated the size of snow particles in clouds at both Martian poles from data gathered by orbiting spacecraft. From their calculations, the group found snow particles in the south are slightly smaller than snow in the north — but particles at both poles are about the size of a red blood cell.“These are very fine particles, not big flakes,” says Kerri Cahoy, the Boeing Career Development Assistant Professor of Aeronautics and Astronautics at MIT. If the carbon dioxide particles were...