An interesting tangent: the size of lenses required to have the same zoom capability as the p900, but on large sensor cameras like the 6D
https://pixelpluck.com/battle-of-biggest-zoom-lenses-ever/I'm not saying that NASA is right, but there is too much evidence in favor of the possibility that NASA is right, not their artistically enhanced images, but real observations that is easily backed by math that at least shows what they say is possible, if not certainly true.
How small is light? If even 1 photon makes it to your camera all night long, that photon had to come from somewhere. How do you rule out it didn't come from a star (assuming we are trying to image stars at night)? Consider how big NASA says the sun is. If stars are that big, and considering how small photons are and how bright the sun is, that is an enormous number of photons released per millisecond of which we only need a grain of sand worth to see. it is very easy for those few rare photons that just happened to be aimed right at earth to reach us in enough quantity to see. It is also not hard to understand how very distant galaxies can be visible when a camera is left to collect light from them over several days at high sensitivity. with a billion stars the size of the sun or larger in one galaxy, as big and spread out as NASA says galaxies are, surely enough photons perfectly aimed at earth will accuмulate over several days to make the image of a faint little galaxy.
Just don't rule it out. You don't have to trust NASA, but I don't see enough evidence to rule it out. If you poke a stick into water, it looks bent, so it is bent right? Wrong.