Although there are many commonalities between them, astronomers have recently come to explain the different appearance of the two most distant planets in the solar system "Uranus" and "Neptune",

The two planets possess similar air blocks, volumes and formulations, yet Neptune appears to be bluer than its neighbour, Uranus.

According to a study by Professor Patrick Erwin at the British University of Oxford, the results of which were published in the journal Geophysical Research, the presence of a layer of fog of different degrees on both planets is behind their different forms.

The study showed that both planets would appear almost equally blue if there was no fog in the atmosphere.

The researchers developed a model for describing aerosol layers in the atmosphere of both planets, using data from the Hubble Space Telescope, NASA Infrared and Jimini North Observatory, and an international team of researchers developed a model for describing aerosol layers in the atmosphere of both planets.

According to Erwin, the model is "the first to simultaneously fit observations of the sun reflected from ultraviolet to near infrared and shows the difference in visible colour between Uranus and Neptune", according to the British newspaper The Independent.

The model includes three layers of fog at different altitudes in the planets' atmosphere.

Scientists say the middle layer of fog particles is thicker on "Uranus" than on "Neptune," affecting the visible colour of two planets.

Methane ice intensifies on molecules in the middle layer on both planets, forming dense layers of methane ice that drag fog particles deeper into the atmosphere.

As Neptune has a more active and volatile atmosphere than Uranus, its atmosphere is more efficient in converting gas to the fog layer, where it can condense on fog particles and produce ice.

This removes more fog, maintains a thinner fog layer for Neptune to appear bluer, while the excess fog on Uranus accumulates in the planet's stagnant and slow atmosphere, giving it a lighter colour.

The research also showed a deeper second layer in the model when blacked out, which may be why dark spots appear occasionally on Neptune more intermittently on Uranus, such as the famous dark spot GDS-89 on Neptune.