Earth

Position	Third from the Sun
Distance from Sun:	149,600,000 km
Earth Day:	24 hours
Earth Year:	365 Earth Days
Orbital Speed:	29.8 km/sec
Eccentricity of Orbit:	0.017
Satellites:	1
Diameter:	12,756 km
Mass:	5.976e24 kg
Major Atmospheric Gas:	Nitrogen

Earth is the fifth largest planet in the Solar System.
The Earth is around 4.6 billion years old.
Earth is the only presently known planet in the Solar System to support life. The earliest fossil evidence for life dates back 3.5 billion years ago.
71% of Earth's surface is covered in water.
The Earth is the densest planet in the Solar System.
The Earth travels at an orbital speed of 108,000 km (67,000 miles) an hour.
The Earth has only one satellite, the Moon. The Moon is the second brightest object in the sky.
The Earth's atmosphere is composed mainly of nitrogen (77%), oxygen (21%), argon (.93%), and carbon dioxide (0.03%).
The surface features on Earth are extremely varied with vast oceans, tall mountains, rolling plains, canyons, swamps, and deserts. The tallest mountain on our planet, Mount Everest in the Himalayas, stands at an altitude of 8,872 m (29,108 ft). Located in Africa, the Sahara, the largest desert on Earth, spans over 500,000 sq km (2,123,000 sq miles) of land. The Grand Canyon, a canyon of multi covered rock terraces cut by the Colorado River, stretches over 350 km (217 miles) of land.
71% of the Earth's surface is coverered in water, which holds vast amounts of ocean life and maintains the temperature of the planet.
Earth has an average surface temperature of 13 degrees C (55.4 degrees F). The planet would be much colder without greenhouse gasses, such as carbon dioxide and water vapor, to trap outgoing thermal radiation. The greenhouse effect raises the planet's temperature 35 degrees C (95 degrees F).
Earth is composed of three layers: a core, a mantle, and an outer crust. The core is composed of two parts: an inner core of solid iron and nickle (2,600 km in diamter), and an outer core made of molten iron and nickle (2,250 km thick). The mantle is partially molten liquid (2,900 km thick). The crust (8 to 40 km thick) is composed of over twenty plates that float on top of the hot mantle. The motion of these plates is called tectonic drift. Tectonic drift is responsible for seafloor spreading and continental drift.

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