Earth is the only planet in the Solar System to have water in its three states of matter: as a solid (ice), a liquid (sea, rain, etc.) and as a gas (clouds). These are all shown below. Water is, of course, the most important liquid for life.
Earth is almost five billion years old, although life (resembling life as we know it) has only existed on the planet for the last 150 million to 200 million years. This means that life has only been present on Earth for only 5%-10% of its lifetime.
Earth and Mercury are the two most dense planets in the Solar System. This means that particles inside the planet are most closely packed together.
The length of time it takes for Earth to orbit the Sun is 365 and a quarter days. To make up this extra quarter which isn't counted at the end of a year, we have an extra day every four years on 29th February. The next Leap Year will be in 2012.
Earth is gradually slowing down. Every few years, an extra second is added to make up for lost time. Millions of years ago, a day on Earth will have been 20 hours long. It is believed that, in millions of years time, a day on Earth will be 27 hours long.
The centre of the Earth, its core, is molten. This means that it is liquid rock which sometimes erupts onto the surface through volcanic eruptions. This core is 7,500°c, hotter than the surface of the Sun!
Earth is the only planet in the Solar System not to be named after a mythical God.
Despite being called Earth, only 29% of the surface is actually 'earth.' The rest of the planet's surface (71%) is made up of water.
From a distance, Earth would be the brightest of the planets. This is because sunlight is reflected off the planet's water.
Earth is the only planet in the Solar System known to be geologically active, with Earthquakes and volcanoes forming the landscape, replenishing carbon dioxide into the atmosphere and erasing impact craters from meteors.
|Name||Earth / Terra / The World|
|Meaning of Name||Planet Earth in the English language is not named after a mythological figure like the other planets. Its name originates from the old English name for the planet, Eorðe (don't ask how to pronounce it!). Its name in many other languages is Terra or similar, named after Tellus, the Roman goddess of Earth, or fertile soil. Its Greek equivalent, Gaea, is Mother Earth|
|Name in Foreign Languages||Terre (French), Tierra (Spanish), Terra (Portuguese, Italian, Latin), Erde (German), Zemlja (Russian), Gaea (Greek)|
|Average Distance from the Sun||149,597,890 km / 92,955,820 miles / 1.000 A.U.|
|Closest Distance to the Sun (Perihelion)||147,100,000 km / 91,400,000 miles / 0.983 A.U.|
|Farthest Distance from the Sun (Aphelion)||152,100,000 km / 94,500,000 miles / 1.017 A.U.|
|Diameter across equator||12,756 km / 7,926 miles|
|Circumference around equator||40,074 km / 24,901 miles|
|Time to spin on Axis||23 hours, 56 minutes|
|Time to orbit the Sun||365 days, 6 hours|
|Distance planet travels to complete one orbit||924,375,700 km / 574,380,400 miles|
|Escape Velocity||40,248 km/h / 25,009 mph|
|Minimum Surface Temperature||-88 °c / -126 °F / 185 K|
|Maximum Surface Temperature||58 °c / 136 ° F / 331 K|
|Weather Conditions||The weather conditions on Earth can vary greatly depending on location and time of year.|
|Contents of Atmosphere||78.1% Nitrogen, 20.9% Oxygen, 0.93% Argon, 0.04% Carbon dioxide, about 1% Water vapor, 0.002% other gases|
|Known moons||1 - The Moon (Luna)|