NLC 2018-08-09/10

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: 2018-08-09/10

   UT     forms  bright   height   azimuth   comments
                  ness   top bot  left rght  e.g. weather
--------  -----  ------  --- ---  ---- ----  --------------------------------
20:30:04  0                                  clear, out of focus
20:45:05  0                                  clear
21:00:05  0                                  clear
21:15:10  0                                  clear
21:30:32  0                                  almost clear
21:45:53  0                                  some cloud
22:01:23  X                                  widespread cloud
22:16:24  X                                  patchy cloud
22:31:25  X                                  patchy cloud
22:46:24  0                                  cloud above h 15
02:01:24  II         2     3        30   35  cloud above h 5
02:16:24  NLC                                through cloud
02:30:47  NLC                                through cloud
02:45:53  X                                  patchy cloud
03:00:33  X                                  widespread cloud
03:15:19  X                                  almost overcast
03:30:08  X                                  almost overcast
03:45:06  X                                  overcast
04:00:05  X                                  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: 2018/08/09-10
Start: 02:00
End: 02:30
Forms: II
Max elevation: 3
Max brightness: 2
Comments: Through cloud.
http://www.chiandh.eu/nlccam/20180809-10.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)
-------- ------ ----- ----- ----- -----  ----- -------------------
02:01:24 30.000  25.8 -15.2  -5.1   3.5  0-255 q4299.jpg
02:16:24 30.000  29.4 -14.3  -4.5   5.2  0-255 q4305.jpg m4305.jpg
02:30:47 15.000  32.8 -13.2  -3.9   7.6  0-255 q4310.jpg m4310.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).