Smoky Moon

The Moon seen through smoke from a nearby forest fire. CREDIT: Stuart
Today, a month-old fire in the Los Padres National Forest flared up and caused rather a lot of smoke to head out towards the coast. That has coincided with an almost full Moon.
If you see the Moon through a big black rain cloud, the Moon doesn't tend to be reddened. However, a black cloud of smoke does redden the Moon. That is because the particles in the smoke cloud are the right sort of size to scatter out the blue light much more than the red light. The result is rather pretty and a nice demonstration of Rayleigh scattering.

The Moon seen through a cloud of smoke, Santa Barbara, California. Six second exposure. CREDIT: Stuart
Posted in astro blog by Stuart on Saturday 28th Jul 2007 (22:10 PDT) | Permalink