User:Hftf/Books/Astro/I–K

I–K

 * Inflation (cosmology)
 * Intermediate spiral galaxy
 * Interstellar cloud
 * Interstellar medium
 * Interstellar reddening
 * Intrinsic redshift
 * Ionization cone
 * Irregular galaxy
 * Jansky
 * Kepler's laws of planetary motion
 * Kirchhoff's law of thermal radiation