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NLC 2011-06-29/30

BAA report

The report to the BAA Aurora Section gives an overview of the night, which times were cloudy, free of NLC, or with sightings of NLC.

Name of observer: Horst Meyerdierks
Location: Royal Observatory Edinburgh, 55.9N 3.2W
          unattended dSLR with limited field of view A ~325-35, h ~0-40
          images every 15 min
Date: 2011-06-29/30

  UT   forms  bright   height   azimuth   comments
               ness   top bot  left rght  e.g. weather
-----  -----  ------  --- ---  ---- ----  --------------------------------
21:45  0
22:00  0                                  cloud on left to h 10
22:15  X                                  some cloud
22:30  0                                  cloud on right to h 15
22:45  0                                  cloud to h 10
23:00  0
23:15  0
23:30  0                                  cloud to h 10
23:45  X                                  cloud to h 10
00:00  II         1    11       340   25  cloud on right to h 8
00:15  II         2    12       338   23
00:30  II,IV      2    10       336   24
00:45  IV         2     9       335  >30
01:00  II,IV      2    10         0  >30
01:15  IV         2    10         0  >30
01:30  III,IV     2    12       344  >30
01:45  I,III,IV   2    13       338  >30
02:00  I,IV       1    12       339  >30
02:15  I          1    10       337  >30
02:30  I          1    10       345   10
02:45  0

forms: I: veil
       II: bands
       III: waves
       IV: whirls
       NLC: other than or multiple of I-IV
       0: no NLC
       X: no decision possible (mist, cloud etc.)
brightness: 1: very weak
            2: clearly detected
            3: clearly visible
            4: very bright
            5: extremely bright

NLCnet report

The periods of positive sightings of NLC are reported to the NLC Observers' Home Page:

Name: Horst Meyerdierks
Country: Scotland
Location: Edinburgh
Date: 2011/06/29-30
Start: 00:00
End: 02:30
Forms: I,II,III,IV
Max elevation: 13
Max brightness: 2
Comments:
<a href="http://www.chiandh.me.uk/p/NLC_2011-06-29/30">Images</a>.

forms: I: veil
       II: bands
       III: waves
       IV: whirls
       O: other than or multiple of I-IV
brightness: 1: very weak
            2: clearly detected
            3: clearly visible
            4: very bright
            5: extremely bright

Images

Listed below are the images with positive sightings of NLC. These have been processed merely to adjust the brightness for underexposure. For some, there may also be an unsharp-masked version of the image.

  UT    exp    A    hSun  h15   h85  stretch  image      (masked)
----- ------ ----- ----- ----- -----  ----- ---------------------
00:00  4.000 356.2 -10.8  -2.4  21.5  0-255 q14768.jpg m14768.jpg
00:15  4.000 359.7 -10.9  -2.5  20.6  0-255 q14772.jpg m14772.jpg
00:30  4.000   3.2 -10.8  -2.5  21.2  0-255 q14776.jpg m14776.jpg
00:45  4.000   6.7 -10.6  -2.3  23.5  0-255 q14780.jpg
01:00  3.200  10.2 -10.3  -2.1  28.6  0-255 q14784.jpg
01:15  2.000  13.7  -9.9  -1.8  39.9  0-255 q14787.jpg
01:30  1.300  17.1  -9.3  -1.4  67.9  0-255 q14789.jpg
01:45  0.600  20.5  -8.7  -0.9 118.6  0-255 q14791.jpg
02:00  0.400  23.9  -7.9  -0.2 149.3  0-255 q14793.jpg m14793.jpg
02:15  0.167  27.3  -7.0   0.7 162.1  0-255 q14795.jpg m14795.jpg
02:30  0.067  30.6  -5.9   2.4 168.5  0-255 q14797.jpg m14797.jpg

exp: Exposure time in seconds (400 ISO, f/3.5).
A: Azimuth of the Sun (degrees).
hSun: Altitude of the Sun (degrees, negative below horizon).
h15: Max. altitude of sunlight at 15 km height (degrees).
h85: Max. altitude of sunlight at 85 km height (degrees).
stretch: Contrast stretch (0-255 means no stretch).