Mauna Loa Solar Observatory
The Mauna Loa Solar Observatory opened in 1965 and housed the K-coronameter (an instrument for observing the solar corona) that had originally been used in Climax, Colorado, at HAO's first location. The Observatory perches on a shoulder of Mauna Loa, a volcanic island, leading to some exciting moments for staff. MLSO has been evacuated a few times because of volcanic eruptions.