Uranus and Neptune: We may now know why the two planets are different shades of blue

Uranus is pale blue in colour while Neptune is a deeper shade of blue, and an atmospheric model can explain the difference



Space



28 January 2022

Uranus and Neptune

Uranus (left) and Neptune (right) imaged by Voyager 2

NASA/JPL-Caltech

Uranus and Neptune are different shades of blue, and we may finally know why.

In visible-light pictures Uranus appears a pale blue, while Neptune is a deeper, cobalt hue. Using data from the Hubble Space Telescope and ground-based observatories, as well as information gleaned from the Voyager 2 spacecraft, Patrick Irwin at the University of Oxford and his colleagues have developed detailed models of the atmospheres of both worlds which might explain the colour difference.

The thick, enshrouding skies of these …