The goal of this research project is to enhance, develop, and publish faint standard star sequences. There is a long-term need for accurate photometric standard stars with known intensities and colors at a variety of optical wavelengths. Use of such standard stars permits the combination and inter-comparison of the brightness and color measurements of different celestial phenomena made by different investigators. Examples of uses include the calibration of magnitudes and color indices of celestial objects to further the understanding of stellar evolution, ages and distances of star clusters, studies of variable stars, and to define the distance scale through our Milky Way Galaxy, the local group of galaxies, and onward to the edge of the Universe.
Here, using telescopes at the Cerro Tololo Interamerican Observatory in Chile, Dr. Landolt will complete the development of new standard stars that will be about 100 times fainter than those now available. He will also begin development of the next set of even fainter standard stars at the Kitt Peak National Observatory in Arizona. These calibration stars are needed for, and will be usable by the entire ensemble of the largest ground-based and space-based optical detectors, both presently built, those under construction, and those in the planning stage. The overall goal of this project is to extend the calibration sequences to fainter limits so the limits of interpretation will be scientific, and not those of calibration.
