circumstellar disk

noun

: a ring of gaseous matter surrounding a star

For the next several million years, this brand new solar system retains its circumstellar disk, where planets slowly accumulate into alien worlds.

—Fred Adams and Gregory Laughlin, The Five Ages of the Universe, 1999

As angular resolution improved and it became possible to observe young stars at infrared (IR) wavelengths, the jets were seen to emerge along the polar axes of structures called circumstellar disks that consist of gas and dust orbiting the stars in relatively thin planes.

—C. Robert O'Dell et al., Science, 30 May 1997

compare accretion disk

Word History

First Known Use

1972, in the meaning defined above

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