Scientists have now said that the dark side of the moon may not be dark but turquoise in reality.
The new findings have come from two years of observation by an international team of astronomers who installed a telescope and a sensitive camera at the Mauna Loa Observatory in Hawaii, which is run by the US National Oceanic and Atmospheric Administration, the Guardian reported.
The dark side of the moon is not lit directly by sunlight, but by the light that is reflected from Earth. It is much fainter, and can best be seen around the time of the new moon.
To measure the colour, the astronomers first screened out light from the bright side that was scattered by Earth's atmosphere. This scattered light produces a shifting halo around the moon and messes up dark side's measurements.
The scientists clicked moon's images through the telescope using two different colour filters.
Amid hundreds of pictures, the astronomer found a pair which was taken of the waning crescent moon on 18 January 2012 that had the same halo. When they subtracted one image from another, the halo disappeared and they could measure the true colour of the moon's dark side.
The study is set to be published in the journal Astronomy and Astrophysics.
