Explanation irregular they show no trace of circular

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Explanation: Irregular. They show no trace of circular or rotational symmetry. Their appearance is irregular and chaotic: The continuity of the morphological forms of galaxies along classification sequences suggests that these different forms might represent stages of _______________ for galaxies. Explanation: Evolution. Elliptical galaxies may always have been elliptical, but they may have had supergiant stars when they were young. Spirals may never become elliptical, but eventually their spiral arms may disappear when virtually all of their interstellar matter is converted into stars. However, the evolution of galaxies is still speculative due to the youth of Astronomy. ______________ of galaxies can be roughly classified into two categories: regular clusters and irregular clusters. : Clusters. Almost all galaxies may be members of groups of clusters. Clusters of galaxies are now regarded as fundamental condensations of matter in the universe. The ______________ clusters have spherical symmetry and show marked central concentration. : Regular. They tend to be very rich clusters and most of them probably contain at least a thousand members. The regular clusters have structures resembling those of globular star clusters. Regular clusters consist almost entirely of elliptical galaxies. The _____________ clusters, sometimes called open clusters, have a more formless appearance and possess little or no spherical symmetry or central concentration. Irregular. The irregular clusters sometimes have several small sub-condensations and resemble loose swarms of small clusters. They contain all kinds of galaxies --- spirals, elliptical, and irregulars. Irregular clusters are more numerous than the regular clusters and range from rather rich aggregates of more than a thousand galaxies to small groups of a few dozen members or less.
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Below is the Virgo Cluster, the closest cluster of galaxies to our Milky Way Galaxy: The cluster of galaxies to which our galaxy belongs is called the __________ group. : Local. The Local Group comprises over thirty-five galaxies. The two most massive galaxies of the Local Group are the Milky Way and the Andromeda Galaxy. Beyond the Local Group, at distances of a few times its diameter, we find other similar small groups of ____________. Explanation: Galaxies. The nearest rich cluster of neighboring galaxies is the Virgo cluster, so named because it is in the direction of the constellation Virgo. Comprising approximately 1,300 member galaxies, the cluster forms the heart of the larger local Local Supercluster, of which the Local Group is an outlying member. Considerable matter exists in _______________ space that is not associated with a galaxy or cluster. Explanation: Intergalactic. It is assumed that such matter exists outside any specific area for three reasons: If galaxies have formed from gas and dust, some of this pre-galaxian material could well have been left over; individual, rapidly moving stars occasionally escape from galaxies and from star clusters; and collisions or tidal interactions
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Explanation Irregular They show no trace of circular or...

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