Crescent Moon. Coloured optical image of a waxing crescent Moon. Two large dark seas" or maria are visible in the sunlit area: Mare Crisium (above) and Mare Fecunditatis (below). They are low-lying plains formed by lava flows after large impacts. This image was taken with the CFH12K camera at the Canada-France-Hawaii Telescope on Mauna Kea, Hawaii. A deep red filter was used to compensate for the Moon's relative brightness compared with most astronomical objects."