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disk

galactic
Also known as: disk component

Quick Summary

The disk is a prominent component of spiral galaxies, including our own Milky Way. It's a flat structure extending from the galactic center, containing stars, gas, and dust. This disk has a thickness roughly one-fifth of its diameter.12

Within the disk, there's a "thin disk" composed of gas, dust, and younger stars, and a "thick disk" with older stars. Spiral arms, which are a key feature of the disk, are also present. Dust clouds are concentrated in the disk's plane and are often most visible within the spiral arms.134

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