T
- T Tauri Stars
- Telescope
- Thales
- Thermal Doppler Broadening
- Thermal Radiation
- Thick Disk
- Thin Disk
- Tidal Tails
- Time Average
- Tired Light
- Toomre Sequence
- Trans-Neptunian Objects
- Transverse velocity
- Trigonometric Parallax
- Triple Alpha Process
- Trojan Asteroids
- Tropic Of Cancer
- Tropic Of Capricorn
- Tropical Year
- Type Ia Supernova
- Type Ia Supernova Explosion Mechanism
- Type Ia Supernova Light Curves
- Type Ia Supernova Progenitors
- Type Ib Supernova Spectra
- Type Ic Supernova
- Type II Supernova
- Type II Supernova Light Curves
- Type IIn Supernova