So You’re Underwater: Why Do You See That Circle of Light Above You?
by Rhett Allain from Feed: All Latest on (#6Q6D0)
Snell's window is one of the coolest phenomena in the natural world. You've seen it, but do you know what causes it?Snell's window is one of the coolest phenomena in the natural world. You've seen it, but do you know what causes it?