Larger elliptical galaxies typically have a system of globular clusters
This traditional portrait of elliptical galaxies paints them as galaxies where the star formation was over after the initial burst, now shining only with their aging stars. No significant evolution was thought to happen.
Some recent observations have found young, blue star clusters inside a few elliptical galaxies, along with other structures that can be explained by galaxy mergers. In the new vision (still quite experimental), an elliptical galaxy is the result of a long process where one or more smaller galaxies, of any type, collide and fuse in a larger one.
This fusion process may at time carry on until recent or contemporary ages, and is not limited to giant ellipticals. For example, our own Milky Way is known to be "digesting" a couple of small galaxies right now.
External links
Elliptical Galaxies (http://www.seds.org/messier/elli.html), SEDS Messier pages
Giant ellipticals, such as M87, may contain over 10 trillion solar masses in the form of stars, are among the largest of galaxies, and are often found at the heart of rich clusters of galaxies.
Dwarf ellipticals, on the other hand, such as M32 (a satellite of the Andromeda Galaxy) may have masses as low as 10 million solar masses and lie at the bottom end of the galactic size range.
It used to be thought that ellipticals were the oldest galaxies, but more recent studies, including computer simulations, suggest that they have formed from collisions and mergers between spiral galaxies.
This traditional portrait of ellipticalgalaxies paints them as galaxies where the star formation was over after the initial burst, now shining only with their aging stars.
Dwarf ellipticalgalaxies are probably not true ellipticals at all; they have properties that are similar to those of irregulars and late spiral-type galaxies.
Ellipticalgalaxies tend to lie in the cores of galaxy clusters and in compact groups of galaxies.
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