Although just a speck in the Milky Way galaxy, Earth is truly a unique planet. Besides being the only planet known to support life, Earth is also the only planet in our solar system with liquid water on the surface, covering 70 percent of the surface.

Earth’s atmosphere protects us from incoming meteoroids and is just the right thickness to keep us warm. Although Earth has only one atmosphere, it consists of six different layers.

Facts about Earth:

Earth houses more than 7.5 billion people and is the only planet known to support life. Earth’s atmosphere is composed mainly of nitrogen and oxygen. 

The rotation of the planet's liquid iron core generates a powerful magnetic field. This magnetic field funnels charged particles from the sun into Earth's atmosphere at both poles. The particles excite gases in the atmosphere, producing lights in the sky we know as aurora borealis and aurora australis.

Earth statistics:

• Distance from the sun: 150 million km (93 million mi)

• Diameter: 12,756 km

• Mass: 5,972,190,000,000,000,000,000,000 kg

• Time for one full orbit ("year"): 365.2 days

• Time for one full rotation ("day"): 24 hours

• Water covers 71% of Earth's surface