This is exactly the reason. Properly exposed with a camera, you cannot see stars near the moon. This is exactly the same effect. There are probably not any sta

This is exactly the reason. Properly exposed with a camera, you cannot see stars near the moon. This is exactly the same effect. There are probably not any stars of high enough magnitude to be visible on the same exposure with such a bright object. In fact, there are definitely not: otherwise, we would see them on the image. For more proof, check out some earlier navigation images taken by New Horizons as it approached pluto, greatly overexposing Pluto and Charon in order to see the stars around them: https://twitter.com/NewHorizonsBot/status/615264675975065600 https://twitter.com/NewHorizonsBot/status/615264675975065600 It's difficult to imagine Pluto, being so far out, being "bright," but remember that light intensity falls off at an inverse square rate with distance. New Horizons being so close to pluto, it's actually an extremely bright object relative to the stars behind it. In fact, NASA did a fun twitter experiment where they gave people the exact time at their location on Earth when it would appear as bright as noon on Pluto. You can see many resulting images here, illustrating how bright the Pluto surface might look were you standing on it: https://twitter.com/search?q=%23plutotime https://twitter.com/search?q=%23plutotime