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

Instead, the analysis turned up hundreds of neutrinos that came from the galactic plane of the Milky Way.

From New York Times • Jun. 29, 2023

In the 1980s he and his colleagues discovered the first known filaments—streaks of superfast particles that stretch vertically through the galactic plane for more than 100 light-years and remain unexplained.

From Scientific American • Jun. 22, 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