1. The date was chosen as the anniversary of the June 30, 1908 Siberian Tunguska event, the most harmful asteroid-related event in recent history.
2. There are thought to be a million asteroids in the solar system which could hit Earth and destroy a city, yet we have discovered fewer than 10,000.
3. The word asteroid, meaning star-like, was coined by William Herschel in 1802.
4. Asteroids are small rocky bodies smaller than planets in interplanetary space.
5. They are thought to be leftovers from the formation of planets about 4.5 billion years ago.
6. Every day, more than 100 tons of material from comets and asteroids falls toward Earth. Most burns up in our atmosphere forming shooting stars. If it reaches the ground, it is a meteorite.
7. The largest asteroid is Ceres which is 587 miles across. It was upgraded to “dwarf planet” in 2006.
8. The impact of the Tunguska asteroid was about 1,000 times that of the Hiroshima atomic bomb.
9. Nasa is currently tracking more than 1,600 asteroids seen as “potentially hazardous” but the chance of any hitting us soon is almost zero.
10. Asteroids is an anagram of O! Disaster.