Why does Neptune have a dark spot?

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Tags

1. #brighter
2. #several
3. #persist
4. #great
5. #cloud
6. #lower
7. #structures
8. #stable
9. #features
10. #vortex
11. #thought
12. #altitudes
13. #troposphere
14. #occur
15. #upper
16. #neptune
17. #methane
18. #months
19. #spots
20. #represent