interstellar space

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The space between the stars. The interstellar matter that occupies this space constitutes several percent of the Galaxy's total mass and it is from this matter that new stars are formed. The matter is primarily hydrogen, in which a number of other molecules and radicals have been detected, together with small solid dust grains. On average the density of matter in interstellar space is about 106 hydrogen atoms per cubic metre, but the gas is not uniformly distributed, being clumped into interstellar clouds of various sizes and densities.

Subjects: Physics.

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