Calais Observatory, Astronomical observatory in Calais, Maine, US
Located in Meridian Park, the observatory features two granite structures, including a transit stone and an eight-foot-tall clock stone for mounting astronomical equipment.
The observatory emerged in the mid-1800s as part of the United States Coast Survey project to establish accurate longitude measurements for mapping purposes.
The site represented early American scientific advancement, contributing to national efforts in astronomical observations and geographical coordinate determination across New England.
The remaining stone pillars and NOAA plaque serve as markers for visitors interested in exploring the early developments of astronomical research in Maine.
The observatory achieved recognition as one of the most precisely located places in the United States during its longitude determination in 1866.
Location: Calais
GPS coordinates: 45.18480,-67.28080
Latest update: March 18, 2025 07:52
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