Earth
Our home, Earth is the only place we know of so far that’s inhabited by living things. It's the only world in our solar system with liquid water on the surface.
Equatorial Diameter
12,756 km
Avg. Temperature
15°C
Mass
5.97219 × 1024 kilograms
Surface Gravity
9.807 m/s²
Rotation Period
23h 56m
Orbital Period
365.25 Days
Axial Tilt
23.4°
Moons
1
Planetary Structure
Earth is composed of several layers. The solid silicate rock crust and the rigid upper mantle form the lithosphere. This lithosphere is broken into a series of tectonic plates that "float" on a more elastic part of the mantle, with their motion giving rise to earthquakes and volcanism. The mantle is a rocky shell that accounts for 84% of the planet's volume. Below this is the liquid outer core, whose convection currents power the Earth's magnetic field. At the center is the dense, solid inner core. Although its temperature is thought to be as hot as the Sun's surface, the extreme pressure prevents it from becoming liquid.
Scientific Discoveries
- Earth is the densest of the eight planets in the Solar System and the largest of the four terrestrial planets.
- The planet's magnetic field is generated in the molten outer core, creating a protective magnetosphere that deflects harmful particles from the solar wind.
- Earth's axial tilt of 23.4° is responsible for producing seasonal variations in climate and weather across the planet during the course of a year.
- The Earth's rotation is gradually slowing, lengthening our day by 1.8 milliseconds per century.
- About 71% of the Earth's surface is covered by salt water oceans, and more than 80% of these oceans remain unexplored and unmapped.
- Earth is the only planet not named after a Greek or Roman god.