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NLC 2018-06-22/23

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: 2018-06-22/23

   UT     forms  bright   height   azimuth   comments
                  ness   top bot  left rght  e.g. weather
--------  -----  ------  --- ---  ---- ----  --------------------------------
21:45:01  0                                  patchy cloud to h 20
22:00:05  0                                  patchy cloud to h 20
22:15:05  X                                  patchy cloud to h 20 or 25
22:30:07  X                                  patchy cloud to h 20 or 30
22:45:08  X                                  patchy cloud
23:00:09  NLC?                               patchy cloud
23:15:10  I          2                       through cloud
23:30:03  I,II       3                       through cloud
23:45:09  I,II,III   3                       through cloud
00:00:10  II,III     3    18      <325   35  through cloud
00:15:18  II,III     3    20      <325  >35  through cloud
00:30:10  I,II,IV    4    20      <325  >35  through cloud
00:45:10  I,IV       4    25      <325       cloud to h 5 or 10
01:00:09  I,IV       4    25      <325       cloud to h 5 or 10
01:15:10  I,II       3    30      <325   10  patchy cloud
01:30:09  II         2                       through cloud
01:45:09  X                                  widespread patchy cloud
02:00:06  X                                  widespread patchy cloud
02:15:05  X                                  widespread cloud
02:30:05  X                                  widespread cloud
02:45:04  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: 2018/06/22-23
Start: 23:00
End: 01:30
Forms: I,II,III,IV
Max elevation: 30
Max brightness: 4
Comments: Through cloud.
http://www.chiandh.eu/nlccam/20180622-23.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)
-------- ------ ----- ----- ----- -----  ----- -------------------
23:00:09  2.000 342.7  -9.1  -1.2  88.2  0-255 q9955.jpg m9955.jpg
23:15:10  2.000 346.1  -9.6  -1.7  50.4  0-255 q9957.jpg m9957.jpg
23:30:03  1.000 349.6 -10.1  -2.0  34.5  0-255 q9959.jpg
23:45:09  2.000 353.1 -10.4  -2.2  27.4  0-255 q9964.jpg
00:00:10  2.000 356.6 -10.6  -2.3  24.3  0-255 q9968.jpg
00:15:18  4.000   0.1 -10.6  -2.3  23.4  0-255 q9973.jpg
00:30:10  2.000   3.6 -10.6  -2.3  24.4  0-255 q9976.jpg
00:45:10  2.000   7.1 -10.4  -2.2  27.6  0-255 q9980.jpg
01:00:09  2.000  10.5 -10.1  -2.0  34.8  0-255 q9984.jpg
01:15:10  2.000  14.0  -9.6  -1.6  51.4  0-255 q9988.jpg
01:30:09  2.000  17.4  -9.1  -1.2  90.0  0-255 q9991.jpg m9991.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).