- the group of galaxies, at least 25 of which are known, that includes the Milky Way.
Origin of Local Group
First recorded in 1915–20
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- astronomy the cluster of galaxies to which our galaxy and the Andromeda Galaxy belong
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A group of more than 30 galaxies that includes 2 large spiral galaxies-the Milky Way and Andromeda-as well as numerous smaller galaxies, many of which are dwarfs. The Local Group has a diameter of approximately 10 million light-years, with its gravitational center located between our galaxy and the Andromeda galaxy. It is part of a larger grouping known as the Virgo supercluster.
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