They know all of the stars and constellations in the night sky
They can tell the time, date, and their location simply by looking at the sky.
They have the ability to summon miniature stars which can be thrown like a weapon; the stars, however, dissipate quickly.
They are able to turn into pure star light for a short time during the night or during the day if in the presence of Astraeus or Asteria or one of their children. While in this state, the user is granted flight and immune to all attacks; however, once the user changes back they will be extremely drained and immobile for a long time.
They have the ability to summon a cluster of miniature stars directly in front of them which can be used to block incoming attacks; the stars, however, dissipate quickly.
They have the ability to create temporary light sources, similar to concept of a flare, which will alight an area for a short time.
They can see perfectly in the night as if it were day.
When the stars are out, they always know their location.
They are innately stronger during the night.
As they are nymphs they do not age, remaining eternally young.
Star Nymphs are generally not connected to a specific star so their life force is not as at risk as that of a tree or flower nymph. However, they can still be killed in battle or of serious injuries.
They have a telepathic/empathetic connection with nature and other nymphs.