circumstellar

American  

[sur-kuhm-stel-er] / ˌsɜr kəmˈstɛl ər /

adjective

1. surrounding a star.

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Etymology

Origin of circumstellar

First recorded in 1950–55; circum- + stellar

Explanation

Things, conditions, or phenomena that are circumstellar revolve around or exist in the region around a star. For example, some stars have circumstellar disks of gas, dust, and debris orbiting them. In addition to circumstellar disks, there are circumstellar winds — streams of particles that flow outward from a star. Astronomers also talk about "circumstellar habitable zones," where conditions around a star can support life as we know it. The star at the center of our solar system is the Sun; of the planets orbiting the Sun, only Earth is in its circumstellar habitable zone, while Venus and Mars are on the edges of it. Circumstellar is built from circum-, "around," and stellar, "of the stars."

Example Sentences

See Examples For:

circumstellar

This source became known as Fomalhaut cs1, short for circumstellar source 1.

From Science Daily ● Jan. 7, 2026

This marks where the supernova blast wave is ramming into surrounding circumstellar material.

From Science Daily ● Dec. 12, 2023

Teams of astronomers were able to detect that circumstellar material for 2023ixf as the supernova expanded outward and crashed into it, producing a discernible shockwave.

From Scientific American ● Jul. 21, 2023

Protostars are often surrounded by circumstellar disks, vast ring-shaped accumulations of gas and dust that will eventually coalesce into planets and moons when the solar system reaches a later stage of evolution.

From Salon ● Mar. 15, 2023

The star is embedded in a shroud of dust and gas that obscures our visible-light view of a circumstellar disk around the star.

From Textbooks ● Oct. 13, 2016