Siderophobia

Siderophobia is the morbid phobia (fear) of celestial stars.

Causes
There are not many known causes for this fear, as it isn't very well-known in itself. A potential cause of this fear is the belief that following the stars will lead to your demise, undoing, death or some kind of bad event. Some others think stars are a sign of bad luck. It couldalso  link to childhood experiences and other such things. For example, a child could witness a shooting star while very young and think it will kill them or loved ones, leading to the overall phobia and the lasting avoidance with looking at the night sky. Another source could be the immense number of stars, which might cause fear in more anxious people, especially kids of a young age. A final reason that could cause this fear might be the belief that each orb in the nighttime sky represents a dead person's soul. This is presumably the potential cause that makes the most sense. It could bring out the realization of how many dead people there are, which may provoke a chain reaction leading to the thought of how short life is.