Point Reyes Milky Way

Explanation: Northern winter constellations and a long arc of the Milky Way are setting in this night skyscape looking toward the Pacific Ocean from Point Reyes on planet Earth's California coast. Sirius, alpha star of Canis Major, is prominent below the starry arc toward the left. Orion's yellowish Betelgeuse, Aldebaran in Taurus, and the blue tinted Pleiades star cluster also find themselves between Milky Way and northwestern horizon near the center of the scene. The nebulae visible in the series of exposures used to construct this panoramic view were captured in early March, but are just too faint to be seen with the unaided eye. On that northern night their expansive glow includes the reddish semi-circle of Barnard's Loop in Orion and NGC 1499 above and right of the Pleiades, also known as the California Nebula.

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The sky would glow like a giant repeating rainbow. Airglow. Air glows all the time, but it's hard to see. A storm may cause a noticeable rippling in the Earth's atmosphere. When a rock is thrown in water, it creates waves in the air. Red airglow is caused by OH molecule that is excited by the sun's UV rays, while orange and green airglow is caused by oxygen and sodium atoms higher up. The photographer noticed the central band of the Milky Way in China a few years ago. The sensitive camera image showed airglow bands to be quite prominent and span the entire sky. The colors are more vibrant thanks to the enhanced featured image.