Circumzenithal Arc

  Arco Circumzenital – Um Sorriso no Céu A Grin in the Sky An Circumzenithal Arc paints the sky this morning, few minutes before a dark gray raining day. A “smile in the sky,” aka a circumzenithal arc, Friday, over Portugal, by Paulo Pereirahttps://t.co/rN9Jskm5Cn pic.twitter.com/dnzYr5Vza0 — EarthSky (@earthskyscience) January 25, …