In our solar system, Uranus is described as having a cyan or aquamarine color attributed to atmospheric methane; Neptune a deeper blue color at least in part due again to methane. During the day, Earth's sky has a blue appearance to a ground-based observer (due to Rayleigh scattering.)
Because its atmosphere has a blue colour.
Neptune
Neptune is the blue planet in the Solar System. The blue color comes from the methane gas in Neptune's atmosphere.
Neptune's atmosphere is made up of hydrogen, helium and methane. The methane in Neptune's upper atmosphere absorbs the red light from the sun but reflects the blue light from the sun back into space. This is why Neptune appears blue.
The gas that gives Uranus its blue color is methane. Methane in the planet's atmosphere absorbs red light wavelengths, leaving the blue and green wavelengths to scatter and create the planet's distinctive color.
Jupiter
Because its atmosphere has a blue colour.
Both Uranus and Neptune have methane in their atmosphere which absorbs red light, allowing the blue hues to be reflected. Neptune is a lot more of a blue colour than Uranus, but Uranus has more methane in its atmosphere. Its though that other constituents in Neptune enrich its blue colour.
Neptune's atmosphere is blue but it has some clouds. They are like white streaks and are scattered all over the planet Neptune.
Neptune
I would think Saturn.
The planet Neptune appears blue, due to the presence of methane in its atmosphere which absorbs red light and reflects blue light. It also has faint, narrow rings surrounding it.
Neptune is the blue planet in the Solar System. The blue color comes from the methane gas in Neptune's atmosphere.
Neptune's atmosphere is made up of hydrogen, helium and methane. The methane in Neptune's upper atmosphere absorbs the red light from the sun but reflects the blue light from the sun back into space. This is why Neptune appears blue.
The gas that gives Uranus its blue color is methane. Methane in the planet's atmosphere absorbs red light wavelengths, leaving the blue and green wavelengths to scatter and create the planet's distinctive color.
The Earth is called the blue planet because when viewed from space, the majority of its surface is covered by water, giving it a blue appearance. The reflection of the oceans and atmosphere causes the planet to appear blue when seen from a distance.
It depends a bit on what the question means. Sometimes Earth is called the blue planet because it looks mainly blue, because of the oceans. Also, Neptune is blue because of the methane in its atmosphere. Uranus is a bluish green colour too. Overall, I think "Neptune" is the best answer.