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The Earth is the third planet from the Sun and was the only planet we know of to support life until 2015, when people discover salt water in Mars. The Earth is the planet we live on, and supports more than seven billion people. Without it, there is no other place we know of to be able to allow us to thrive and survive as we do today. It is the fifth largest planet, has the fifth largest moon, and the fifth fastest rotating planet.
The Earth was formed by nebula gases leftover from the formation of the Sun. The gases formed a solid from rotating around in a pattern and compacting together in a process called accretion.
After the gases formed the Earth, the Earth was in a state where numerous meteorites collided with the Earth. This was the state the Earth was in before the cooling process began. This state was called the late heavy bombardment period. This period ended when a Mars-sized object called Theia collided with the Earth, causing trillions of tons of Earth to fly into air. Somewhat, this would later create the Moon. Earth then was cooled by celestial particles that floated to the surface.
This then created the Earth we know now.
Venus, the Earth's neighboring planet, is classified as its "sister" because of its similar size and shape. They are exact opposites though. Venus is a planet of volcanic activity and the surface are filled with lava. Earth, on the other hand, is 70.6% water and can support life. Venus and Earth are not the best set of siblings as you can see.
The Earth's atmosphere is mostly made of nitrogen. In fact, more than three fourths of the atmosphere is nitrogen. Oxygen makes up just more than one-fourth of the atmosphere. The rest is made up of less than one percent argon and carbon dioxide.
The atmosphere is split into two main layers: the troposphere and the stratosphere. The troposphere is the closest layer of the atmosphere to us. All of the weather on Earth occurs in this layer. The stratosphere is the lowest layer of the mesosphere, and is where the temperature of the atmosphere begins to increase due to the absorption of ultraviolet radiation from the Sun. This layer is also rich with ozone, for it contains a portion of the ozone layer.
Other layers include the mesosphere, the region in the atmosphere at which the temperatures drop to below -100 degrees Fahrenheit due to radiation being reflected away from this layer into the stratosphere. This layer is where the majority of the ozone layer is found. The ozone layer is the layer created by the build up of ozone, which is a gaseous substance that absorbs most of the ultraviolet radiation from the Sun.
Clouds are another addition in the atmosphere. These occur when air in the troposphere begins to rise and then fall. The cool air falls since it is more dense and the warm air rises because it is less dense. This process is called convection. When water vapor rises, it becomes heated and continues rising because it becomes less dense. Then, once it rises above the clouds, it cools and condenses, becoming clouds.
|Name||Oceans Water||Creating||Creating Year||Created Thing||Life|
|Earth||Salltly||With Meteors||4.5 bilion years ago||Asteroid||Yes|
List of spacecrafts who orbited Earth Edit
|Giotto||ESA||2 July 1990||22,730 km|
|Galileo||NASA||8 December 1990||301 km|
|Sakigake||ISAS||8 January 1992||88,790 km|
|Suisei||ISAS||20 August 1992||failure|
|Galileo||NASA||8 December 1992|
|Sakigake||ISAS||14 June 1993
28 October 1994
|NEAR Shoemaker||NASA||23 January 1998||540 km|
|Nozomi||ISAS||20 December 1998||1000 km|
|Giotto||ESA||1 July 1999||failure|
|18 August 1999||1171 km|
|Stardust||NASA||15 January 2001||6000 km|
19 June 2003
|Hayabusa||ISAS||19 May 2004||20,000 km|
|Rosetta||ESA||4 March 2005||1950 km|
|MESSENGER||NASA||2 August 2005||2348 km|
|Stardust||NASA||15 January 2006|
|Rosetta||ESA||13 November 2007|
|Deep Impact||NASA||31 December 2007
|Stardust||NASA||14 January 2009||9200 km|
|Rosetta||ESA||13 November 2009|
|Deep Impact||NASA||June 2009
|Juno||NASA||9 October 2013||559 km|
|Hayabusa 2||JAXA||3 December 2015|
|PROCYON||University of Tokyo
|3 December 2015|
|Shin'en 2||Kyutech||4 December 2015|
|OSIRIS-REx||NASA||22 September 2017||17,237 km|
=== By spaceport ===
Mercury • Venus • Earth • Mars • Jupiter • Saturn • Uranus • Neptune