Concept
Warm Ionized Medium
Diffuse ionised gas spread through the galactic disc.
Low-density ionised hydrogen at ~10,000 K filling much of the galaxy's volume, illuminated by hot stars and OB associations.
Overview
Low-density ionised hydrogen at ~10,000 K filling much of the galaxy's volume, illuminated by hot stars and OB associations.
See also
Strömgren Sphere
The ionised bubble around a hot star.
Warm Neutral Medium
Diffuse warm hydrogen filling much of the galaxy.
Moving Group
Stars sharing a common motion through the galaxy.
Meridian
The great circle through the zenith and the poles.
The Big Bang
How everything began, 13.8 billion years ago.
Black Holes
Regions where gravity stops light itself.