The Ukiah Latitude Observatory, one of five globally along the 39 parallel, measured the wobble of the earth on its axis. Continuous astronomical observation were made from 1899 to 1983 when modern technologies made nightly observations unnecessary.
City of Ukiah
WELCOME TO OBSERVATORY PARK
Observatory Park was deeded to the City of Ukiah in 1991 by the US Department of Commerce after 83 years of continuous astronomical observation by the U.S. Coast and Geodetic Survey.
The small wood-framed structure at the south entrance to the park on Observatory Avenue played a key role in the scientific investigation of the Earth’s rotation. In 1898, the International Geodetic Association established a network of observatories to measure the wobble of the planet on its axis by plotting the locations of specific stars. This spot in Ukiah was chosen together with sites in Gaithersburg Maryland, Italy, Japan, and the Russia. All five lay along the same latitude (39° 8’ N).
The park is preserved as an open space “for the quiet enjoyment of the residents of Ukiah” and to provide clear ground and satellite views of small brass survey monuments located on the grounds. Though technology rendered the nightly observations by resident astronomers unnecessary, the survey monuments are still referred to today as benchmarks to determine aberrations in of the earth’s motion.
