What Is a Comet Made Of?
A new method for looking at the composition of comets using ground-based telescopes has been developed by chemists at UC Davis. Remnants from the formation of our solar system, the makeup of comets gives clues about how the Earth and other planets formed. William Jackson, professor and chair of chemistry at UC Davis; researchers Alexandra Scodinu and Dadong Xu; and Anita Cochran of the University of Texas at Austin have developed methods to use visible and ultraviolet spectroscopy to study the chemical composition of comets. Spectroscopy, a powerful technique in chemistry, splits light into a spectrum of color. Chemicals show a distinct pattern of peaks or lines in a spectrum. But the emission spectrum of comets in the visible and ultraviolet bands is full of thousands of lines, making it difficult to identify any one component. The researchers took one suspected chemical, carbon disulfide, and used spectra measured in the laboratory under conditions similar to those in a comet. They c
