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            Observing 
              tips: Look 
              west 30 to 60 minutes after sunset when 
              the Sun has dipped 6o to 16o below the horizon. 
              If you see luminous blue-white tendrils spreading across the sky, 
              you've probably spotted a noctilucent 
              cloud. Although 
              noctilucent clouds appear most often at high latitudes such as Scandinavia 
              and Canada, they have been sighted 
              in recent years as far south as Colorado, Utah and Virginia. NLCs 
              are seasonal, appearing most often in late spring and summer. In 
              the northern hemisphere, the best time to look would be between 
              mid-May and the end of August. See also 2003, 
              2004, 2005 
              and 2006. | 
           
         
        
           
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                   Photographer, 
                    Location | 
                   Images | 
                   Comments | 
                 
                 
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                   Morten 
                    Ross,  
                    Sandbukta, Svartskog, facing Oslo, Norway 
                    Aug. 4, 2007 | 
                   #1, 
                    #2, 
                    #3, 
                    more | 
                     The 
                      mellow and slow moving NLCs were present in the northwest 
                      after sunset, as opposed to northeast before sun rise most 
                      of the other times I've seen NLCs. Will this be the last 
                      of the season..?  
                    Photo 
                      details: Nikon 
                      D70, ISO 200, F/3.5, 13sec @ around 00:40 local time 
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                   Tom 
                    Eklund,  
                    Valkeakoski, Finland 
                    Jul. 30, 2007 | 
                   #1, 
                    more | 
                     This 
                      panorama was composed from 10 vertical images shot with 
                      a Nikon 
                      D200 and a 28mm lens. At around 3 AM the display reached 
                      closer to the southern horizon than the zenith.   | 
                 
                 
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                   P-M 
                    Hedén,  
                    Vallentuna, Sweden 
                    Jul. 30, 2007 | 
                   #1, 
                    more | 
                     Another 
                      fantastic display of NLC!!! I was up all night watching 
                      these wonderful "clouds" and they changed in structure and 
                      brightness all night.....a moment to remember!  
                    Photo 
                      details: 20mm Sigma objective, Canon 
                      Digital Rebel XT on a tripod.   | 
                 
               
              
              more 
                images (July 30): from 
                Morten Ross of Sandbukta, south of Oslo, Norway 
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