Many scientists believe that an asteroid impact caused the extinction of the dinosaurs around 65 million years ago.
The solar system formed around 4.6 billion years ago.
The Moon appears to have more craters and scars than Earth because it has a lot less natural activity going on, the Earth is constantly reforming its surface through earthquakes, erosion, rain, wind and plants growing on the surface, while the moon has very little weather to alter its appearance. Saturn the only ringed planet, other gas giants such as Jupiter, Uranus and Neptune also have rings, they are just less obvious.
Footprints and tyre tracks left behind by astronauts on the moon will stay there forever as there is no wind to blow them away.
In 2006, astronomers changed the definition of a planet. This means that Pluto is now referred to as a dwarf planet.
Because of lower gravity, a person who weighs 200 pounds on earth would only weigh 76 pounds on the surface of Mars.
The only planet that rotates on its side like a barrel is Uranus. The only planet that spins backwards relative to the others is Venus.
Some of the fastest meteoroids can travel through the solar system at a speed of around 42 kilometers per second (26 miles