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  1. Home
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  3. Interstellar Medium
Astrophysics

Interstellar Medium

Definition

The matter and radiation between star systems, consisting primarily of hydrogen and helium gas with dust particles. It plays a crucial role in star formation, as new stars form from the collapse of dense regions within it.

Related Terms

Nebula

A giant cloud of dust and gas in space, often spanning light-years. Nebulae are star birthplaces, forming when regions c...

Star

A massive, luminous sphere of hot gas held together by gravity, generating energy through nuclear fusion. Stars range fr...

Galaxy

A gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. Galaxies range from ...

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Full Glossary

Browse all 66+ space and astronomy terms.

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