Two major branches of space science is astronomy and aerospace engineering.
Astronomy[]
- Astronomy
- Outline of astronomy
- Fields of astronomy defined by approach
- Observational astronomy – Observatories on the ground as well as space observatories take measurements of celestial entities and phenomena
- Astrometry – studies the position and movements of celestial objects
- Amateur astronomy
- Theoretical astronomy – mathematical modelling of celestial entities and phenomena
- Fields of astronomy defined by approach
- Fields of astronomy defined by scope
- Astrophysics – study of the physics of the universe; of extraterrestrial objects and interstitial spaces
- Space plasma physics
- Orbital mechanics or astrodynamics, which also has applications to spacecraft
- Stellar astronomy – the study of stars
- Solar astronomy – the study of our Sun
- Planetary science – the study of planets, especially those other than Earth
- Planetary geology
- Galactic astronomy – the study of our Milky Way galaxy
- Extragalactic astronomy – the study of the larger universe beyond the Milky Way
- Physical cosmology – the study of the Universe as a whole
- Astrophysics – study of the physics of the universe; of extraterrestrial objects and interstitial spaces
- Outline of astronomy
Aerospace engineering[]
- Aerospace engineering
- Astronautics
- Aeronautics