Evolution of Neptune's atmosphere, page 5
On this scale you can see that the "rocky" materials such as Calcium, Magnesium, Iron, Nickel, and Lead, that the terrestrial planets are made of can condense out of a very hot nebula, but ice will not condense unless the temperature is very low.
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The solar system contracted, or shrank together, out of a spinning cloud of hydrogen and helium gas. This spinning cloud had a certain amount of momentum, which caused it to flatten, somewhat the way a
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This image shows the new Great Dark Spot of Neptune, which was discovered using the Hubble Space Telescope. The image shown here, shows a "hole" in the clouds of Neptune in pink, in the northern hemisphere,
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Atmospheres of the giant planets have definitely evolved from their formation out of the primitive solar nebula. How much they have evolved remains to be seen, however. Because of their enormous gravity,
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This image shows some cirrus clouds, extending for many kilometers across the disc of Neptune. These clouds are somewhat high up, for they can be seen to cast shadows on the lower clouddeck, which is 35
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This image of Neptune uses false colors to bring out the hazes of smog, which can be seen in red along the limb of Neptune, at the edge of the picture. These hazes of smog are found at very high altitudes,
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Like Jupiter and all the giant planets, Neptune's appearance shows a striped pattern of clouds. Other cloud shapes seen over time include a small dark spot, the "scooter" and the Great Dark Spot. The Great
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If you had a quiz question in school that asked what year Neptune was discovered, you'd probably choose 1846. But Neptune wasn't discovered the way all the other planets in our solar system were. Astronomers
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In astronomy, it is a usual procedure to calculate the luminosity of a star, and this calculation indicates the energy and the temperature of the star. When the luminosity of the outer planets was calculated,
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