On March 25, 1655, Saturn's moon Titan was discovered by the Dutch scientist Christiaan Huygens (a name that you've probably heard mispronounced as "Hoy-gens"). Titan is the largest moon of Saturn ...

A good example of this is furnished by Huygens' principle, which in its original form discusses the propagation of light by asserting that the wave front is the envelope of secondary waves whose ...