Why can we see stars in the pictures of spacewalking or moonwalking astronauts?
The stars aren’t visible because they are too faint. The astronauts in their white spacesuits appear quite bright, so they must use short shutter speeds and large f/stops to not overexpose the pictures. With those camera settings, though, the stars don’t show up. The same thing happens if you try to take a picture of someone under a dark, starry sky. To get the person perfectly exposed, you have to use a flash or some other light source, and set your camera accordingly. When you do that, there is no way to see the stars in the background. To see the stars, you need long exposures and wide-open aperatures. But with those settings, the subject of the picture would appear dark and blurry. Astronauts have taken many photographs of the stars from orbit (and many of them are available on NASA’s web site, but, unfortunately, not with spacewalking astronauts in the foreground.
