Galaxy Classification
When stars are viewed through a telescope, they continue to appear as bright points of light without any apparent size or structure. However, there are some objects in the sky that, viewed through a telescope, look like ÒfuzzyÓ clouds. Some of these are the star forming regions called nebulae, which we have already discussed. Others, like those shown in the Hubble Space Telescope image to the right, are actually islands of stars that are much farther from us than the individual stars we see in the night sky. Although Immanual Kant first advanced the idea of Òisland universesÓ during the eighteenth century to explain observed compact clouds, is was not until this century that astronomers began to develop an understanding of the nature of galaxies.

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