Galaxies are beacons that cosmologists use to chart the universe out to its remotest depths. Yet unlike a lighthouse, built on a sturdy pillar of rock, a galaxy resembles an island of light constructed on quicksand in a continuous state of flux. Galaxies are not isolated objects, but are surrounded by close companions, with whom they often maintain intimate and ongoing relationships. The oldest stars in a galaxy are nearly as old as the universe itself, and a study of their properties yields clues about how galaxies evolved in the distant past. The galaxies themselves define space in the expanding universe. In this article, I will describe current ideas on how galaxies originated and acquired their observed forms, and how this knowledge promises to lead to insights into the evolution of the large‐scale structure of the universe.
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April 1987
April 01 1987
The Formation of Galaxies
Investigation of how these luminous islands evolved and acquired their current forms may lead to insights into the large‐scale structure of the universe as well.
Physics Today 40 (4), 28–35 (1987);