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Located or originating beyond the Milky Way.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Astronomy) occurring or existing beyond the Galaxy
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌɛk strə gəˈlæk tɪk)

outside the Milky Way system.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Adj.1.extragalactic - outside or beyond a galaxy; "extragalactic nebula"
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
PhD student Dan Pryer who has already started working on the project, on the 'extragalactic helpdesk', says:
Dr Elisabeta Lusso, from the Centre for Extragalactic Astronomy at Durham University, said: "Black holes are the most luminous persistent sources of the universe and allow us to measure its expansion rate at very early times.
Contributed by scientists from around the world, the 29 papers and poster sessions address topics like the properties of variable stars in the Milky Way, stellar populations in nearby galaxies, and the application of stellar population studies to the extragalactic distance scale and implications for observational cosmology.
It is a powerful observatory that has provided enormous amounts of data on gamma rays (the most energetic form of light) and their interaction with the extragalactic background light (EBL), which is a cosmic fog composed of all the ultraviolet, visible and infrared light emitted by stars or from dust in their vicinity.
A few words of caution: Extragalactic globulars lack the optical impact of familiar ones in the Milky Way so are best appreciated with your mind as well as your eyes.
Now, as part of the same effort, a team of researchers working at Breakthrough Listen, a project to search for extraterrestrial intelligence signals (SETI), has detected as many as 72 FRBs - all coming from a mysterious extragalactic source located 3 billion light-years away from Earth.
Second, he has sex with a giant extragalactic cockroach and, in the process, becomes a hero, single-handedly solving the galaxy's need for a new source of faster-than-light travel after the Qhigarians, a species who previously controlled all hyperjumps with their minds, leave the galaxy.
Lead author Dr Richard Massey, from Durham University's Centre for Extragalactic Astronomy, said: "The search for dark matter is frustrating, but that's science.
While planets are often discovered within the Milky Way using microlensing, the gravitational effect of even small objects can create high magnification leading to a signature that can be modeled and explained in extragalactic galaxies.
'Although the possibility that FRBs are produced by extragalactic civilizations is more speculative than an astrophysical origin, quantifying the requirements necessary for an artificial origin serves, at the very least, the important purpose of enabling astronomers to rule it out with future data,' the pair said in the conclusion of their study.
They were trying to decipher the extragalactic background light, or EBL, a diffuse glow that fills the universe (SN:9/7/13, p.