http://en.wikipedia.org/wiki/Opposition_surgeIn the case of the Moon, B. J. Buratti et al. have suggested that its brightness increases by some 40% between a phase angle of 4° and one of 0°, and that this increase is greater for the rougher-surfaced highland areas than for the relatively smooth maria.
http://the-moon.wikispaces.com/AlbedoThe NASA Moon Fact Sheet gives the visual geometric albedo of the Moon as 0.12. However this number probably doesn't include the opposition surge which can increase the reflectance of the lunar surface by 50% or more when the light source and detector are precisely aligned.
en cualquier caso, anoche me levantaron el gato y el perro. fuera la luna estaba alta, como el sol al mediodía, y había mucha mucha luz. el cielo estaba ligeramente azul.