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arXiv · 0811.2448

Mauna Kea Sky Transparency from CFHT SkyProbe Data

Eric Steinbring·Jean-Charles Cuillandre·Eugene Magnier
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Abstract

Nighttime sky transparency statistics on Mauna Kea are reported based on data from the Canada-France-Hawaii Telescope SkyProbe monitor. We focus on the period beginning with the start of MegaCam wide-field optical imager operations in 2003, and continuing for almost three years. Skies were clear enough to observe on 76% of those nights; attenuations were less than 0.2 magnitudes up to 60% of the time. An empirical model of cloud attenuation and duration is presented allowing us to further characterize the photometric conditions. This is a good fit tothe SkyProbe data, and indicates that Mauna Kea skies are truly photometric (without cloud) an average of 56% of the time, with moderate seasonal variation. Continuous monitoring of transparency during the night is necessary to overcome fluctuations in attenuation due to thin cloud.

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Eric Steinbring, Jean-Charles Cuillandre, Eugene Magnier. 2008-11-15. Mauna Kea Sky Transparency from CFHT SkyProbe Data. https://doi.org/10.1086/597766

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