During World War II, the Fremont Station of the Harvard College Observatory on Ceresco Ridge was strictly off-limits to mine employees, and while no one knew what went on there, Mine Superintendent Jack Abrahms regularly left his office so Observatory Director Walt Robert could use the phone in private. The observatory housed a Lyot-type coronagraph, a specialized telescope used to observe solar flares. Roberts and his staff used the coronagraph to record flare activity, which interferes with radio communications, then coded the data and phoned it to the Western Union office in Leadville, from where it was wired to Washington. Military planners used the information to schedule every major operation of World War II. After the war, the University of Colorado became involved with the operation of the observatory. It was moved to the slopes of Chalk Mountain to escape the town’s lights, and data collected there in the 1960’s was used by NASA to help schedule manned space flights.
