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Our skies are blue due to the scattering of sunlight by Nitrogen & Oxygen. The sky on Mars is pink due to dust blown around in a Carbon Dioxide atmosphere. The moon's sky is dark day and night as there is no air at all. This means stars should be in every picture taken on the moon.
Below; a long exposure photograph taken in Arizona. A long exposure would be required on the moon too. But each picture by Apollo astronauts was taken hand-held with a 1/250 sec setting. No stars would appear on any of the moon pictures; this is perfectly normal! The Earth will appear as it is lit by the sun just as is the moon and would require 1/250 sec exposure too.