Media Information

 
 
 
Collection:
NASA Astronomy Picture of the Day Collection
Title:
Sundogs over the VLA
Explanation:
What if you woke up one morning and saw more than one Sun in the sky? Most probably, you would be seeing sundogs [ http://ww2010.atmos. uiuc.edu/(Gh)/guides /mtr/opt/ice/sd.rxml ], extra-images of the Sun [ http://www.seds.org…] created by falling ice-crystals [ http://dspace.dial.…] in the Earth's atmosphere [ http://csep10.phys.…]. As water freezes in the atmosphere, small, flat, six-sided, ice crystals [ http://kristall.uni…] might be formed. As these crystals flutter to the ground, much time is spent with their faces flat, parallel to the ground. An observer may pass through the same plane as many of the falling ice crystals [ http://www.gi.alask…] near sunrise or sunset. During this alignment, each crystal can act like a miniature lens, refracting [ http://wigner.byu.e…] sunlight into our view and creating parhelia [ http://dspace.dial.…], the technical term for sundogs. Sundogs [ http://www.members.…] were photographed here in a cloudy sky above the Very Large Array [ http://antwrp.gsfc.…] of radio telescopes [ http://casswww.ucsd…]. The real Sun is near the center above the train tracks. A bright sundog [ http://www.gi.alask…] is visible on the far right, and a dim one on the far left. Ice-crystals can create other strange illusions of the Sun and Moon [ http://www.members.…] including halos [ http://ww2010.atmos. uiuc.edu/(Gh)/guides /mtr/opt/ice/halo/22 .rxml ] and pillars [ http://antwrp.gsfc.…]
Credit and Copyright:
Joe Orman [ http://home.cwix.co…]
keyword:
atmosphere
keyword:
VLA
keyword:
sun dogs
facet_where:
Alaska
facet_where:
Goddard Space Flight Center (GSFC)
facet_what:
Earth
facet_what:
Moon
facet_what:
Sun
facet_what:
VLA
facet_what:
Very Large Array
facet_what:
KRISTALL
original url:
UID:
SPD-APOD-ap990823

Sundogs over the VLA