Interstellar medium

Alternative definitions (0), class: vernacular (0)
Term: Interstellar medium

The environment containing the interstellar matter (the gas and dust that exists in open space between the stars), consisting of gas (mostly hydrogen) and dust. Even at its densest phase, the interstellar medium is emptier than the best vacuum man can create in the laboratory, but because space is so vast, the interstellar medium still adds up to a huge amount of mass.

Created 2023.04.16
Last Modified 2023.04.16
Contributed by Ryan McGranaghan