Jim Harwood: Summit Surveyor

John Jefferies, in suit and tie, visits Jim Harwood on Maunakea.during the site survey

In 1965, John Jefferies charged the young physicist Jim Harwood with managing the Maunakea Site Survey to establish the best place to build a major new telescope. (A parallel survey was taking place on Haleakala).

On Maunakea, Harwood’s team used a pair of separated telescopes on a common mounting to form a pair of images of a single star: the “seeing” could then be assessed from the differential motion of the two, thus eliminating the telescope shake, common to both images. Two small Questar telescopes with fine optical quality were also used to determine the diffraction ring stability. Infrared transmission of the overlying atmosphere was measured via the relative depletion of sunlight in two spectral bands.

Five sites were ultimately tested from 12,000 feet to 13,600 feet along the access dirt road. At each site, a framed plywood enclosure was constructed for protection against frequently hazardous weather conditions.

For almost two years, he and his colleagues lived while on duty at the 9,200-foot level, first in the stone cabins that gave the area its name Hale Pohaku, and then in a wood frame hunter’s cabin together with a house trailer salvaged from a missile tracking station at South Point on the Big Island. High, cold, and dangerous, conditions for these pioneers of science were formidable. Harwood recalls being trapped all night inside a van during a major snowstorm on the mountain. Nevertheless he described his time on Mauna Kea as one of “exhilarating adventure.”

In 1966, NASA accepted the site survey recommendations that Maunakea had a distinct advantage over Haleakala, despite the considerable greater development costs.  Had Harwood’s survey results been less convincing than they were, Maunakea Observatory might never have come into existence.

After construction for the University of Hawai‘i 2.2 meter telescope began, Harwood complemented his early MKO survey work by making the 2.2-meter telescope the first fully computerized telescope facility in the world.   A strong incentive for computerizing was the 13,700-foot altitude of the observatory, with the resulting 40% oxygen deficit which greatly affected the reliability of human control.

“My experiences on the Maunakea Site Survey, taking complex readings from astronomical and weather instruments night after night in the cold, high, solitary, totally remote environment of unending volcanic terrain with a brilliant canopy of stars overhead, were unforgettable. I was totally dependent for my safety on the 4-wheel drive transport and an observing partner. For every minute we were on the mountain there was an undercurrent of present danger in the alien environment that kept us continuously alert. This was a life experience that I will remember always, especially the fact that it all led to the optimum positioning of a major astronomical telescope on Maunakea.” — Jim Harwood