The speed of movement can be calculated from the change in color. If we look at the 'red-nosed reindeer' pulling Santa's sleigh, when the reindeer approaches, the wavelength becomes shorter and ...

Every year on Christmas Eve, nine reindeer pull Santa’s sleigh through the sky so he can deliver presents to children throughout the world. Their names are Dasher, Dancer, Prancer, Vixen ...

Santa Claus is coming to town ... and in Rio de Janeiro's fashion, he rode a Jet Ski. The city's firefighters and nonprofit associations joined efforts to cheer up children. (AP Video/Lucas ...