The crew of NASA's Gemini 6A space flight got into the Christmas spirit and made history when they played "Jingle Bells" on December 16, 1965, earning the jingle the Guinness World Record for being the first song ever played in space.

The universe is so vast in relation to the matter it contains that it can be compared in the following way: A building 20 miles long, 20 miles wide, and 20 miles high that contains 1 grain of sand.

In the observable universe there are an estimated 2 trillion galaxies.