1) The largest living structure on Earth is the Great Barrier Reef, spanning over 2,300 kilometers (1,400 miles) along the coast of Australia.

2) The Hubble Space Telescope, launched in 1990, has provided breathtaking images of distant galaxies and deep space.

3) The total length of your blood vessels can circle the Earth more than twice.

4) The musical "Les Misérables" is one of the longest-running shows in the West End and Broadway, with over 13,000 performances.