Asked by: TERESA FISHER, BIRMINGHAMThe Moon is actually quite black – it reflects the same amount of light as coal. Even a full Moon is 400,000 times less bright than the Sun. Your retina contains cone and rod receptors. The cones are the only ones that sense colour, but they need higher light intensities to work. The Moon is only bright enough to power the rods, and appears light grey against a black sky.