Why is the Moon white?

To some the Moon appears colourless, or even grey.


Asked by: Edward Seymour, Hove

Despite appearances, the Moon is not entirely devoid of colour. Apollo astronauts described its colour as ‘brownish’. Careful study shows that the dark areas, or ‘maria’, display hints of blue or brown while the highland areas have faint traces of yellow, pink and pale blue. These differences are mainly due to varying amounts of metals such as iron or titanium in the surface minerals.

Unfortunately, the human eye isn’t sensitive enough to pick out these slight differences in colour from a distance. However, much of the lunar surface contains minerals that are naturally grey and these dominate the colour we perceive from Earth.

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