Micrometeorites

During the period of Curtis L. Hemenway's directorship, the main work of the Dudley Observatory shifted from observational astronomy to space science. Research centered around the study of cosmic dust in the upper atmosphere and in space. The analysis of micrometeorites to determine their origin formed the bulk of the research performed over the next decades. Micrometeorites are tiny particles less than one-ten-thousandth of a meter in diameter that bombard the earth from space. Efforts included collecting micrometeorites with apparatus flown on high altitude aircraft, balloons, and spacecraft, and analyzing the collected materials using such tools as electron microscopes.

Dudley's first major contract was awarded in 1959 by the Air Force Cambridge Research Center. In the early part of 1961, a NASA grant supported balloon-borne sampling devices in the Sesame project. Sounding rockets were used for the same purpose in the Pandora program. In the 1970's, Dudley developed experiments and sampling devices that were included in the Apollo, Gemini, Skylab guest experiment programs. Balloons continued to be used in the Magellan project in which circumpolar flights were made from a base in Australia. Contracts and grants to fund research in this general area came from NASA, the National Science Foundation, and the AFCRC. Complementary research areas included the sublimation of ice particles, meteor spectroscopy, particle formation, and ultra high resolution spectroscopy.