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NLC 2018-08-03/04

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: 2018-08-03/04

   UT     forms  bright   height   azimuth   comments
                  ness   top bot  left rght  e.g. weather
--------  -----  ------  --- ---  ---- ----  --------------------------------
20:45:04  0                                  some cloud patches, out of focus
21:00:05  0                                  some cloud patches
21:15:06  0                                  some cloud patches
21:30:09  0                                  cloud to h 10
21:45:20  0                                  cloud to h 10
22:00:53  0                                  cloud to h 10
22:16:30  I          1    10       325       cloud to h 10 on right
22:32:34  I          1     8      <325       cloud to h 10 on right
22:47:33  I          1     5      <325       cloud to h 10 on right
23:02:34  I          1     5      <325       cloud to h 10 on right
23:17:33  0                                  some cloud
23:32:33  X                                  some cloud
23:47:33  X                                  almost clear
01:02:34  X                                  clear
01:17:33  0                                  clear
01:32:33  0                                  almost clear
01:47:34  II         2     4        25   35  almost clear
02:02:33  I,II       1     5            >35  some cloud and haze
02:16:24  I          2    10            >35  some cloud and haze
02:30:53  I,II       2    12       330  >35  some cloud and haze
02:45:32  I,II,III   2    20       325  >35  some cloud and haze
03:00:19  I,II,III   2    40                 cloud to h 10
03:15:06  NLC        1    50                 cloud to h 15
03:30:05  X                                  cloud and haze to h 30
03:45:02  X                                  cloud and haze to h 30

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: 2018/08/03-04
Start: 22:15
End: 03:15
Forms: I,II,III
Max elevation: 50
Max brightness: 2
Comments: Some cloud.
http://www.chiandh.eu/nlccam/20180803-04.shtml

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)
-------- ------ ----- ----- ----- -----  ----- -------------------
22:16:30 30.000 330.2 -12.3  -3.4  10.7  0-255 q3712.jpg m3712.jpg
22:32:34 60.000 333.9 -13.4  -4.0   7.2  0-255 q3718.jpg m3718.jpg
22:47:33 60.000 337.5 -14.3  -4.5   5.2  0-255 q3724.jpg m3724.jpg
23:02:34 60.000 341.1 -15.0  -4.9   3.9  0-255 q3730.jpg m3730.jpg
01:47:34 60.000  21.8 -14.4  -4.6   4.9  0-255 q3772.jpg m3772.jpg
02:02:33 60.000  25.4 -13.6  -4.1   6.7  0-255 q3778.jpg m3778.jpg
02:16:24 30.000  28.7 -12.7  -3.6   9.2  0-255 q3783.jpg
02:30:53 15.000  32.1 -11.7  -3.0  13.9  0-255 q3789.jpg
02:45:32  8.000  35.4 -10.6  -2.3  24.7  0-255 q3794.jpg
03:00:19  4.000  38.8  -9.3  -1.4  70.0  0-255 q3797.jpg
03:15:06  1.000  42.1  -8.0  -0.3 146.9  0-255 q3799.jpg m3799.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).