It sounds a bit confusing. But all we ever knew about quasars was that they were very small ( a few light years across) and very energetic objects located billions of light years away. This distance was far beyond where we could previously detect individual galaxies like our Milky Way, but now times have changed as our technology has gotten better. Astronomers can now photograph galaxies, at least the brighter ones, that are as far away as the most distant quasars were know to be only 15 years ago. Theoreticians long ago predicted that the 'quasar phenomenon' is a process that is happening in the nuclei of certain kinds of galaxies. The latest results from the Hubble Space Telescope (see image above) now show that many of the nearer quasars are accompanied by smudges of light that look like galaxies; with the quasar located in the center of the galaxy.
It now seems very likely that we shall continue to detect galaxies nearly all the way out to the 'edge' of the visible universe to see images of them as they were just being born. We will also continue to see, and resolve, the host galaxies of more and more distant quasars out to the same limiting distance. Galaxies will be seen to be formed through out this range of distances, and for reasons we still do not understand, a few of these infant galaxies will erupt as quasars.
Copyright 1997 Dr. Sten Odenwald
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