HD c - high
- HD curve
- HD system
- He+ ionization zone
- head tail galaxies
- heat transfer
- heavy elements
- heavy metal stars
- heliocentric correction
- heliocentric Julian date
- heliocentric orbits
- heliocentric parallax
- heliocentric velocity
- heliographs
- heliometers
- heliopause
- helioseismology
- heliosphere
- heliostats
- helium burning
- helium detonation
- helium flash
- helium poor stars
- helium rich stars
- helium shell flash
- helium variable stars
- Helmholtz Kelvin contraction
- Henry Draper catalog
- Henry Draper system
- Henyey track
- Herbig Haro objects
- Herbig stars
- Hertzsprung gap
- Hertzsprung Russell diagram
- Hess diagram
- heterodyne
- HH objects
- hierarchical cosmology
