Mauna Loa Solar Observatory (MLSO)
Mauna Loa Solar Observatory (MLSO) acquires unique observations of the Sun’s atmosphere to support NCAR’s goal to address critical gaps in understanding the Sun-Earth system and to provide observations to reduce damage and disruption from space weather hazards.
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Mauna Loa Solar Observatory is reopening in April 2026! In November 2022, MLSO was closed due to a volcanic eruption that buried parts of the access road to the Observatory. Restoration of the road is now underway and expected to be completed by early April. Following access restoration, we expect MLSO to begin K-Cor observations and CME alert services within 3–4 weeks. UCoMP observations and data services will commence shortly thereafter. See the Mauna Loa volcano eruption page.
NCAR/HAO’s Mauna Loa Solar Observatory will support the Artemis II mission by alerting NASA’s Space Radiation Analysis Group of solar Coronal Mass Ejections (CMEs) that are the root cause of radiation storms in space. MLSO measures CME velocity and direction — key parameters for determining if a CME will cause a radiation storm — on average one hour before NOAA’s operational CCOR coronagraphs on the GOES or Solar-1 satellites. This critical extra lead time enables SRAG operators and the Artemis II crew to plan mitigating actions that can protect the crew from harmful radiation in space.
