This is an image of Neptune, and shows the Great Dark Spot.
Click on image for full size
NASA
Neptune Clouds, overview
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 Dark Spot is the largest of the cloud patterns on Neptune. There are also clouds which are similar to recognizable terrestrial clouds, such as
cirrus clouds. The clouds are found in the troposphere of Neptune.
The atmosphere of Neptune is composed mostly of methane.
Hazes of smog on Neptune, made of methane and other, even more complex molecules, are to be found at very high altitudes above the clouds of Neptune.
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