1) The word "country" contains three vowels: O, U, and Y.

2) The Great Barrier Reef, situated off the coast of Queensland, Australia, is the largest coral reef system in the world. It stretches over 2,300 kilometers (1,400 miles) and is home to a diverse array of marine life, making it a popular destination for diving and snorkeling.

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

4) The blue whale is the largest animal to have ever existed, with an average length of about 82 feet (25 meters).