Atmospheric Optics
- Provides a detailed look at a wide variety of optical effects in the atmosphere.
- http://www.atoptics.co.uk/

Red Sunset, Green Flash
- Tells why sunsets look red, and why you can sometimes see a green flash just before the sun sets.
- http://hyperphysics.phy-astr.gsu.edu/hbase/atmos/redsun.html