Hubble classification system

American  

noun

1. Astronomy. a framework for categorizing galaxies according to their shape, the main types being elliptical, spiral, barred spiral, lenticular, and irregular.

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Hubble classification system Scientific  

1. A system developed by Edwin Hubble in 1936 that classifies galaxies as elliptical, spiral, barred spiral, lenticular, and irregular. Hubble speculated that galaxies might fit into an evolutionary sequence from earlier elliptical galaxies to later spiral forms, but most astronomers no longer believe this is the case. Our galaxy, the Milky Way, is a spiral galaxy.

2. Also called Hubble sequence

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