protogalaxy — [prōt΄ō gal′ək sē] n. pl. protogalaxies in some cosmological theories, a huge cloud of dust and hydrogen gas out of which millions of protostars are formed protogalactic [prōt΄ōgə lak′tik] adj … English World dictionary
Protogalaxy — In physical cosmology, a protogalaxy, which could also be called a primeval galaxy , is a cloud of gas which is forming into a galaxy. It is believed that the rate of star formation, during this period of galactic evolution, will determine… … Wikipedia
protogalaxy — noun Date: 1950 a cloud of gas believed to be the precursor to a galaxy … New Collegiate Dictionary
protogalaxy — noun A cloud of gas which is starting to form a galaxy … Wiktionary
protogalaxy — pro·to·galaxy … English syllables
protogalaxy — n. hypothetical cloud of gas from which present galaxies are thought to have formed … Dictionary of difficult words
protogalaxy — … Useful english dictionary
galaxy — /gal euhk see/, n., pl. galaxies. 1. Astron. a. a large system of stars held together by mutual gravitation and isolated from similar systems by vast regions of space. b. (usually cap.) See Milky Way. 2. any large and brilliant or impressive… … Universalium
Galaxy — This article is about the astronomical structure. For other uses, see Galaxy (disambiguation). NGC 4414, a typical spiral galaxy in the constellation Coma Berenices, is about 55,000 light years in diameter and approximately 60 million light… … Wikipedia
Galaxy groups and clusters — are the largest known gravitationally bound objects to have arisen thus far in the process of cosmic structure formation.[1] They form the densest part of the large scale structure of the universe. In models for the gravitational formation of… … Wikipedia
