This is a schematic showing how atmospheres form.
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The Origin of an Atmosphere
There are four ideas for the origin of a planetary atmosphere. Those four ideas are 1. that the planet-elements of which a planet was made released the atmosphere, 2. that the atmosphere was drawn to the planet from the gaseous cloud out of which everyth
ing came, 3. that comets hit the planet and brought molecules of air with them, 4. that volcanoes erupted and made an atmosphere from gases inside the planet.
The one that applies to Uranus is hypothesis #2, in which the original material, which Uranus drew out of the primitive nebula stayed, and forms the atmosphere today.
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As shown in this picture, while they were forming in the solar nebula, the nucleii of the planets-to-be (called protoplanets) drew material to themselves from the cloud of gas and dust around them. The
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Besides methane, Uranus' atmosphere contains even more complex molecules such as ethane gas. (These gases are similar to the exhaust gases that come out of cars on earth). These molecules form layers of
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The mesosphere of Uranus is a region of balance between warming and cooling. That essentially means that nothing happens there. Except for diffusion, the atmosphere is still. Upper reaches of the atmosphere,
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As on Earth, the atmosphere of Uranus consists of a troposphere, stratosphere, mesosphere, and thermosphere. The troposphere is the region where the visible clouds are to be found. The stratosphere, as
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On Uranus, as on Jupiter, the winds in the belts and zones blow first in one direction, then in the opposite direction. Wind blows east in a belt, and west in a zone. The clouds rise up in a belt, and
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The clouds on Uranus, like Jupiter, are divided into belts and zones. On Uranus the belts and zones are hard to find. The left picture shows the north pole of Uranus. In this picture only the smog of
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The clouds of Uranus, composed of methane crystals, are found very low in the atmosphere, and are difficult to see below the smog haze s of the planet. False color is used, in the image of Uranus to the
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