Neptune colour

[kidlands]

As I understand it Neptune is blue because of the depth of its methane layer, I know methane absorbs red light but does it also absorb green light hence Neptune it is bluer than Uranus.

[toml42]

Uranus is the colour we would expect from methane absorption. In short, no one knows why Neptune is a deeper shade of blue, it's hypothesised it may be to do with additional elements or compounds in the atmosphere, the colder temperatures or the weather systems, or maybe something else entirely.

This question bugs me, too!