Why Neptune and Uranus appear in different shades of blue

Subject: Science and Tech

Section: Space

Neptune and Uranus have much in common — they have similar masses, sizes, and atmospheric compositions — yet their appearances are in different shades of blue.
At visible wavelengths, Neptune is a rich, deep azure hue, while Uranus is a distinctly pale shade of cyan.
Reason:
- Haze around Uranus is thicker than that around Neptune: Uranus’s stagnant, sluggish atmosphere and makes it appear a lighter tone than Neptune
  - There are three aerosol layers in the atmospheres of Neptune and Uranus.
  - The key layer that affects the colours is the middle layer, which is a layer of haze particles that is thicker on Uranus than on Neptune.
  - Methane ice condenses onto the particles in this layer, pulling the particles deeper into the atmosphere.
  - Because Neptune has a more active, turbulent atmosphere than Uranus does,thus Neptune’s atmosphere is more efficient at churning up methane particles into the haze layer.
  - This removes more of the haze and keeps Neptune’s haze layer thinner than it is on Uranus, with the result that the blue colour of Neptune looks stronger.