galactic plane

American  

noun

Astronomy.

1. the plane of the galactic equator.

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galactic plane British  

noun

1. the plane passing through the spiral arms of the Galaxy

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Etymology

Origin of galactic plane

First recorded in 1840–50

Example Sentences

The right panel shows a side view, cutting vertically through the galactic plane.

From Science Daily • Oct. 22, 2025

But because the signals emanate from the crowded galactic plane, optical telescopes could not see which of many stars might be producing them.

From Science Magazine • Dec. 3, 2024

We found, surprisingly, a distribution of filaments parallel to the galactic plane.

From Scientific American • Jun. 22, 2023

The new filaments are shorter — a few light-years in length — and they run in a different direction, parallel to the galactic plane rather than through it.

From New York Times • Jun. 8, 2023

Globular clusters plunge through the galactic plane and out the other side, where they slow, reverse and hurtle back again.

From "Cosmos" by Carl Sagan