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Astronomy

The Lifecycle of Interstellar Gas Clouds

Quick fact

The typical density of an interstellar gas cloud is about 1,000 atoms per cubic centimeter — a billion times thinner than the air you breathe. A cloud spanning dozens of light-years may contain only a few thousand solar masses of material.

Why this is interesting

Every star in the night sky was born from a cold, dark cloud of gas and dust. But where do those clouds come from, and where do they go after a star dies?