Corning Inc. of Corning, N.Y., has announced that it has shipped the 4.3-m primary mirror blank to the Southern Observatory for Astronomical Research at Cerro Pachón in Chile. Constructed of ultralow-expansion glass, the monolithic blank ensures that the final mirror will require little external heating or cooling, simplifying the instrument's adaptive optics system. The final telescope will perform astronomical research in the visible and near- to midinfrared. It is slated to perform spectrophotometry of Cepheid variables to gauge interstellar and intergalactic distances and to detect subsolar masses such as planets by microlensing. The project is a collaborative effort of the University of North Carolina in Chapel Hill, the Laboratório Nacional de Astrofísica of Brazil, Michigan State University in Lansing and the National Optical Astronomy Observatory in Tucson, Ariz.