1) The musical "The Phantom of the Opera" has been running in London's West End since 1986, making it the longest-running musical in history.

2) The discovery of the Americas by Christopher Columbus in 1492 opened up new trade routes and had a profound impact on world history.

3) The first successful portable MP3 player, the Diamond Rio PMP300, was released in 1998 and could hold up to 60 minutes of music.

4) The Northern Lights, also known as the Aurora Borealis, are natural light displays that occur in the polar regions due to interactions between the Earth's magnetic field and solar particles.