Earth formed around 4.6 billion years ago by collisions in a giant disc-shaped cloud of material. Gravity caused this gas and dust to slowly accrete into clumps ,which became the asteroids and small early planets called ... More »

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As the only known planet that is habitable for human beings, the Earth’s importance is self-evident. Every living organism known to science obtains all of its resources from Earth, and has very few other options availabl... More »

An earth tremor is another term for an earthquake, although it is most commonly used to describe earthquakes of low intensity. Earthquakes are measured with tools called seismographs, and their intensity is rated on a lo... More »

Earth formed around 4.54 billion years ago and is the third planet from the Sun. It is the fifth largest planet in the solar system and the largest of the terrestrial planets. It is also the densest of all the planets. More »

The distance between Earth and Uranus changes constantly, due to the solar system not being entirely concentric. However, the closest Earth and Uranus get is 1.6 billion miles, which is 2.6 billion kilometers. At furthes... More »

The hottest place on Earth is in its molten core, where temperatures reach approximately 10,800 degrees Fahrenheit. The surface temperatures on the planet vary widely, but according to NASA, the average surface temperatu... More »

The Earth has a mass of 5.97 times 10^24 kilograms. Because weight is defined as the gravitational force exerted on one body by another, the Earth cannot be heavy. More »