A 3.6 billion-year-old moon rock shines in Washington National Cathedral

Visitors wandering along the nave of Washington National Cathedral can be treated to an unusual sight: a 3.6 billion-year-old moon rock, encased in one of the cathedral's windows. The Apollo 11 astronauts brought back to Earth this piece of the moon, which weighs 7.18 grams and was donated to the cathedral in 1974. Their historic moon landing marks its 50th anniversary on July 20th of this year.