Here's something you don't see too often ... a detailed picture of thefull Moon surrounded by a rich field of background stars. It's true that bright moonlight scattered by the atmosphere tends tomask faint stars, but pictures of th sunlit portionof the Moon madewith earthbound telescopesor even with cameras on th lunar surface often fail to show any backgroun stars at all.Why? Because the exposure times are too short.Very short exposures, lasting fractions of a second, are required toaccuratel recordan image of the bright lunar surface.But the background stars (and galaxies!) such as those visible aboveare much fainter and need exposures lasting minutes to hours whichwould seriously overexposethe surface of the Moon.So, of course this stunning viewreally is a combination of two digital images --a short exposure, registering the exquisite lunarsurface detail at full Moon, superposed ona separate very long exposure, made wit the Moon absent from the star field.The final representatio ofMoon and background stars is verydramatic, even though it could not have been captured in a singleexposure.
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