Question

When viewed through a telescope, Uranus and Neptune are distinctly bluish green in color. What gas is responsible for this striking appearance?

1) helium
2) hydrogen
3) methane
4) water

Answer 1

Methane in the upper clouds of Uranus and Neptune is responsible for their distinct bluish-green color because it scatters blue light from the Sun.

Step-by-step explanation:

The bluish-green hue of Uranus and Neptune, observed through telescopes, results from methane in their upper atmospheres. Methane absorbs red light from the Sun and scatters blue light, creating the planets' distinctive colors. This unique optical interaction between sunlight and methane molecules contributes to their vivid appearance. While both planets share similarities in their atmospheric composition, the specific arrangement of gases and the prevalence of methane set the stage for this striking visual characteristic, highlighting the fascinating interplay of chemistry and light in the outer reaches of our solar system.