Local Galaxy Group

The majority of galaxies1 form groups held together by gravity. Some groups are really gargantuan in size, e. g., groups in Virgo and Berenices Hair constellations feature thousands of galaxies stretched over some 20 million light years.

Smaller galaxy groups do exist, an example is our own galaxy - the Milky Way. This group, called Local Group, comprises some 30 galaxies stretched over some 5 million light years.

The most famous galaxies of the Local Group are Milky Way, Andromeda, and M33 galaxy in the Triangulum constellation.

The groups themselves form less thick groups, called supergroups. The latter are the greatest objects in the Universe, stretched over hundreds of millions of light years.

The Local Group is a part of the Local Supergroup, the center of which is located in the group in Virgo constellation.

The galaxies that have no regular form are called irregular. An example is the Lesser Magellanic Cloud. The irregular galaxies are very small, much less than the Milky Way, yet they contain great amounts of gas from which new stars are formed. The Lesser Magellanic Cloud is among the nearest to the Milky Way, it can be seen in the Southern Hemisphere.

Elliptical galaxies are very few in number in the Local Group, and are only poorly visible. An example is the M87 galaxy from the Virgo Group. It is a big ball made of more than a thousand billion old red stars and a few novas. The stars always move in the same direction in an elliptical galaxy.

NGC1365, part of the Fornax group, is a spiral galaxy with a short bridge comprised of older stars. The ends of bridge feature arms. Such spiral is called a bridge. The bridge rotates as if it were a solid body, however, it is made from millions of separate stars. It is possible that the Milky Way is also such a galaxy.

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