A false-colour Moon
Colour filters can help determine the composition of lunar soil.
The Moon was a focal point for NASA in 2017, whether it was blocking out the Sun during one of the most-viewed events in U.S. history, or reinvigorating the agency’s human space exploration plans. But the Moon has always been a focus of humanity's imagination.
This false-colour image composed of 15 images taken through three colour filters by NASA's Galileo spacecraft, as it passed through the Earth-Moon system on Dec. 8, 1992. When this view was obtained, the spacecraft was 425,000 kilometres from the Moon and 69,000 kilometres from Earth. The false-colour processing used to create this lunar image is helpful for interpreting the surface soil composition. Areas appearing red generally correspond to the lunar highlands, while blue to orange shades indicate the ancient volcanic lava flow of a mare, or lunar sea. Bluer mare areas contain more titanium than do the orange regions.