Search results
Results from the WOW.Com Content Network
Stephan's Quintet is a visual grouping of five galaxies of which four form the first compact galaxy group ever discovered. [2] The group, visible in the constellation Pegasus, was discovered by Édouard Stephan in 1877 at the Marseille Observatory. [3] The group is the most studied of all the compact galaxy groups. [2]
Size (left) and distance (right) of a few well-known galaxies put to scale. There are an estimated 100 billion galaxies in all of the observable universe. [1] On the order of 100,000 galaxies make up the Local Supercluster, and about 51 galaxies are in the Local Group (see list of nearest galaxies for a complete list).
Radio-faint galaxies like M 31 and M33, the Milky Way's neighbors, have weaker fields (about 5 μG), while gas-rich galaxies with high star-formation rates, like M 51, M 83 and NGC 6946, have 15 μG on average. In prominent spiral arms, the field strength can be up to 25 μG, in regions where cold gas and dust are also concentrated.
According to recent studies, the Milky Way as well as the Andromeda Galaxy lie in what in the galaxy color–magnitude diagram is known as the "green valley", a region populated by galaxies in transition from the "blue cloud" (galaxies actively forming new stars) to the "red sequence" (galaxies that lack star formation). Star-formation activity ...
Examples of astronomical objects include planetary systems, star clusters, nebulae, and galaxies, while asteroids, moons, planets, and stars are astronomical bodies. A comet may be identified as both a body and an object: It is a body when referring to the frozen nucleus of ice and dust, and an object when describing the entire comet with its ...
It is also important to consider the morphology of the galaxy when attempting to measure its size – an issue that has been raised by the Russian astrophysicist B.A. Vorontsov-Vel'Yaminov in 1961, which considers separate determination methods in measuring the sizes of spiral and elliptical galaxies. [2] For a full context about how the ...
List of the largest known stars in Andromeda and Triangulum galaxies Star name Solar radii (Sun = 1) Galaxy Method [a] Notes Theoretical limit of star size (Andromeda Galaxy) ≳1,750 [11] L/T eff: Estimated by measuring the fraction of red supergiants at higher luminosities in a large sample of stars. Assumes an effective temperature of 3,625 K.
Computer simulated view of the large-scale structure of a part of the universe about 50 million light-years across [66] Matter continues to draw together under the influence of gravity, to form galaxies. The stars from this time period, known as Population II stars, are formed early on in this process, with more recent Population I stars formed ...