Dr. Herbig will continue his observational research into the nature of diffuse interstellar bands. It includes an effort to correlate the strengths of the diffuse bands with local properties of the interstellar medium through high-precision observations of stars imbedded in ionized hydrogen clouds, of stars behind clouds in which the coatings of the interstellar dust grains have to some extent been removed, and of stars behind shocked interstellar gas. Dr. Herbig wil also search for interstellar polyatomic carbon molecules. These studies depend upon the special advantages of observing from the high altitude site of Mauna Kea in Hawaii. The problem of the identification of the carrier of the diffuse interstellar band (DIB) spectrum remains unsolved over fifty years after it was demonstrated that these features are produced by some constituent of the interstellar medium. With the availability of new detectors the list of diffuse interstellar bands has grown to some 50 sure entries, to which can be added at least 20 more weak features that have recently been found in the red and near infrared regions of the spectrum. Still no convincing regularities in DIB characteristics are apparent. This leads to the suspicion that a family of carriers may be involved. Dr. Herbig's research will address this very vexing problem in astronomy.
