There are nine continents on Earth, all of which are inhabited. These are
- North America
- South America
There is also the subcontinent of Kerguelen (or Lemuria, as it is known in Europe), which is geographically counted as part of Africa, India, Asia, or Oceania. However, it is on a separate tectonic plate.
The planets nearest to Earth are Venus and Mars, which are the third and fifth planets respectively.
Earth is mainly composed of rock and metal, with molten lava at the core and more solid material toward the crust.