General:
* Celestial science: This is a more formal term that encompasses the study of all celestial objects.
* Cosmology: This focuses on the origin, evolution, and large-scale structure of the universe.
* Astrophysics: This delves into the physical properties and processes of celestial objects.
More specific:
* Astrology: This refers to the study of the supposed influence of celestial bodies on human affairs, but it's not considered a science.
* Stargazing: This is a more casual term for observing the stars and other celestial objects.
The best synonym will depend on the specific meaning you want to convey.
