Hertzsprung gap


Hertzsprung gap

(herts -sprûng) A region on the Hertzsprung–Russell diagram, to the right of the main sequence, in which few stars are found. This is because of a star's rapid evolution through this region, away from the main sequence. This occurs during the period when hydrogen is being burnt in a shell around the core of helium, before the onset of helium burning (see stellar evolution). The gap can be easily seen on H-R diagrams of open clusters.

Hertzsprung gap

[′hert·spru̇ŋ ‚gap] (astronomy) A gap on the Hertzsprung-Russell diagram between giant stars of spectral types A0 and G0, caused by the fact that the movement of stars across this region occupies a relatively brief time.