Why do white nights happen?

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Tags

1. #polar
2. #comes
3. #atmosphere
4. #light
5. #sunlight
6. #regions
7. #opposite
8. #because
9. #occurs
10. #beyond
11. #throughout
12. #phenomenon
13. #reduces
14. #there
15. #night
16. #circles
17. #called
18. #under
19. #across
20. #which
21. #scattering