Subj : Daily APOD Report To : All From : Ben Ritchey Date : Fri Dec 21 2018 06:02:25 Astronomy Picture of the Day Astronomy Picture of the Day Discover the cosmos! [1] Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2018 December 21 [2] Extraordinary Solar Halos Image Credit & Copyright [3] : Magnus Edback [4] Explanation: Welcome to the December Solstice, the first day of winter in planet Earth's northern hemisphere and summer in the south. To celebrate, consider this extraordinary display of beautiful solar ice halos! More common than rainbows [5] , simple ice halos can be easy to spot, especially if you can shade your eyes from direct sunlight. Still it's extremely rare to see anything close to the complex of halos [6] present in this astounding scene. Captured at lunchtime [7] on a cold December 14 near Utendal, Sweden the image includes the relatively ordinary 22 degree halo, sundogs (parhelia) and sun pillars. The extensive array of rarer halos [8] has been identified along with previously unknown features. All the patterns are generated as sunlight (or moonlight) [9] is reflected and refracted in flat six-sided water ice crystals in Earth's atmosphere. In this case, likely local contributors to the atmospheric ice crystals are snow making machines operating at at nearby ski center. Tomorrow's picture: pixels in space ------------------------------------------------------------------------------- < [10] | Archive [11] | Submissions [12] | Index [13] | Search [14] | Calendar [15] | RSS [16] | Education [17] | About APOD [18] | Discuss [19] | > [20] ------------------------------------------------------------------------------- Authors & editors: Robert Nemiroff [21] (MTU [22] ) & Jerry Bonnell [23] (UMCP [24] ) NASA Official: Phillip Newman Specific rights apply [25] . NASA Web Privacy Policy and Important Notices [26] A service of: ASD [27] at NASA [28] / GSFC [29] & Michigan Tech. U. [30] ---------- Site notes: [1] archivepix.html [2] image/1812/IMG_8741_cSunHaloEdback2048.jpg [3] lib/about_apod.html#srapply [4] https://www.astrobin.com/users/Magnusedback/ [5] https://science.nasa.gov/science-news/science-at-nasa/ 2002/24oct_sunrings [6] https://www.atoptics.co.uk/halosim.htm [7] http://www.thehalovault.org/2018/12/ complex-halo-display-borlange-sweden.html [8] https://www.atoptics.co.uk/fza164.htm [9] ap150403.html [10] ap181220.html [11] archivepix.html [12] lib/apsubmit2015.html [13] lib/aptree.html [14] https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search [15] calendar/allyears.html [16] /apod.rss [17] lib/edlinks.html [18] lib/about_apod.html [19] http://asterisk.apod.com/discuss_apod.php?date=181221 [20] ap181222.html [21] http://www.phy.mtu.edu/faculty/Nemiroff.html [22] http://www.phy.mtu.edu/ [23] https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html [24] http://www.astro.umd.edu/ [25] lib/about_apod.html#srapply [26] https://www.nasa.gov/about/highlights/HP_Privacy.html [27] https://astrophysics.gsfc.nasa.gov/ [28] https://www.nasa.gov/ [29] https://www.nasa.gov/centers/goddard/ [30] http://www.mtu.edu/ --- Mystic BBS v1.12 A40 (Windows/32) * Origin: FIDONet - The Positronium Repository (1:393/68) .