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NLC 2019-06-21/22

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 compact camera with limited field of view
          A ~325-35, h ~0-40; images every 15 min
Date: 2019-06-21/22

   UT     forms  bright   height   azimuth   comments
                  ness   top bot  left rght  e.g. weather
--------  -----  ------  --- ---  ---- ----  --------------------------------
21:45:04  0                                  some cloud to h 5
22:00:05  II         1    45  15   350  >35  some cloud to h 5
22:15:02  II         2    45  15   335  >35  some cloud to h 5
22:30:02  II         3   >45  15   325  >35  some cloud to h 5
22:45:02  II,III     3   >45  15   325  >35  some cloud to h 5
23:00:08  II         3   >45  15   325  >35  some cloud to h 5
23:15:18  II,III     3   >45  15   325  >35  some cloud to h 5
23:30:33  II,III     2    35  15   330  >35  some cloud to h 5
23:45:32  II         1    30  15   300  >35  some cloud to h 5
00:00:32  II         1    30  15   350   30  some cloud to h 5
00:15:32  0                                  some cloud to h 5
00:30:32  0                                  some cloud to h 5, fake NLC at centre
00:45:32  0                                  some cloud to h 5, fake NLC on right
01:00:32  0                                  some cloud to h 5
01:15:19  0                                  some cloud to h 5
01:30:09  0                                  some cloud to h 5 or 10
01:45:08  0                                  some cloud to h 5 or 10
02:00:06  X                                  some cloud
02:15:06  X                                  widespread cloud
02:30:05  X                                  widespread cloud
02:45:05  X                                  almost overcast

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: 2019-06-21/22
Start: 22:00
End: 00:00
Forms: II,III
Max elevation: >45
Max brightness: 3
Comments: some cloud to h 5
http://www.chiandh.eu/nlccam/20190621-22.html

forms: I: veil
       II: bands
       III: waves
       IV: whirls
       NLC: 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)
-------- ------ ----- ----- ----- -----  ----- -------------------
22:00:05  0.125 329.3  -5.6   3.1 169.9  0-255 q8024.jpg m8024.jpg
22:15:02  0.250 332.6  -6.6   1.2 164.6  0-255 q8025.jpg m8025.jpg
22:30:02  0.500 335.9  -7.6   0.1 155.1  0-255 q8027.jpg
22:45:02  1.000 339.3  -8.4  -0.7 134.3  0-255 q8029.jpg
23:00:08  2.000 342.7  -9.0  -1.2  90.4  0-255 q8032.jpg
23:15:18  4.000 346.2  -9.6  -1.6  51.6  0-255 q8035.jpg
23:30:33  8.000 349.7 -10.1  -2.0  34.9  0-255 q8039.jpg
23:45:32  8.000 353.2 -10.4  -2.2  27.9  0-255 q8043.jpg
00:00:32  8.000 356.7 -10.6  -2.3  24.7  0-255 q8047.jpg

exp: Exposure time in seconds (200 ISO, f/2.8).
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).