For 25 years, Krucz has been developing computer programs for studying the atmosphere and composition of stars. His most widely used programs are ATLAS, for modeling characteristics of stellar atmospheres, and WIDTH, for computing the individual lines in a stellar spectrum, information that is then used to determine the relative amounts of various elements in the star.
Krucz's first attempt at modeling stellar atmospheres took place in 1965, when he was a senior at Harvard University. He tried to compute the composition and atmospheric opacity of a star, but "it didn't work very well," he recalls. "For the last 25 years I've been trying to fix it!" During that time, Krucz has been steadily adding spectroscopic data to his programs. "Recently," he says, "I've been developing new stellar models for various abundances [of elements], ranging from very low-metal stars, like those formed when the galaxy was young, to abundances like ...
