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 NASA Astronomy Picture of the Day (2024-11-19): Undulatus Clouds over Las Campanas Observatory
https://apod.nasa.gov/apod/image/2411/ParallelClouds_Beletsky_960.jpg
What's happening with these clouds?  While it may seem that these long and thin clouds are pointing toward the top of a hill, and that maybe a world-famous observatory is located there, only part of that is true. In terms of clouds, the formation is a chance superposition of impressively periodic undulating air currents in Earth's lower atmosphere. Undulatus, a type of Asperitas cloud, form at the peaks where the air is cool enough to cause the condensation of opaque water droplets.  The wide-angle nature of the panorama creates the illusion that the clouds converge over the hill.  In terms of land, there really is a world-famous observatory at the top of that peak: the Carnegie Science's Las Campanas Observatory in the Atacama Desert of Chile.  The two telescope domes visible are the 6.5-meter Magellan Telescopes.  The featured coincidental vista was a surprise but was captured by the phone of a quick-thinking photographer in late September.   Your Sky Surprise: What picture did APOD feature on your birthday? (post 1995)