chi and h site logo

NLC 2019-06-25/26

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: 2019-06-25/26

   UT     forms  bright   height   azimuth   comments
                  ness   top bot  left rght  e.g. weather
--------  -----  ------  --- ---  ---- ----  --------------------------------
21:45:04  X                                  cloud to h 10 or 15
22:00:04  X                                  cloud to h 5 or 15
22:15:05  X                                  cloud to h 5, to h 25 on right
22:30:06  X                                  cloud to h 10 or 15
22:45:02  X                                  cloud to h 10 or 15
23:00:09  X                                  cloud to h 10 or 15
23:15:19  X                                  cloud to h 15
23:30:32  X                                  cloud to h 5
23:45:32  X                                  cloud to h 5
00:00:32  X                                  cloud to h 5
00:15:32  II         2     5      <325  340  NLC just above cloud bank
00:30:32  II         2     8      <325  340  NLC just above cloud bank
00:45:32  II         2    10      <325  340  cloud to h 5 on left
01:00:31  II         2    10      <325  335  cloud to h 5
01:15:19  II         1    10      <325  330  cloud to h 5
01:30:09  0                                  cloud to h 5
01:45:07  0                                  cloud to h 5
02:00:06  0                                  cloud to h 5
02:15:06  X                                  cloud to h 15 or 25
02:30:05  X                                  almost overcast
02:45:05  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: 2019-06-25/26
Start: 00:15
End: 01:15
Forms: II
Max elevation: 10
Max brightness: 2
Comments: above cloud bank
http://www.chiandh.eu/nlccam/20190625-26.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)
-------- ------ ----- ----- ----- -----  ----- -------------------
00:15:32  8.000 360.0 -10.7  -2.4  23.0  0-255 q8283.jpg
00:30:32  8.000   3.5 -10.6  -2.3  23.8  0-255 q8287.jpg
00:45:32  8.000   7.0 -10.4  -2.2  26.9  0-255 q8291.jpg
01:00:31  8.000  10.5 -10.1  -2.0  33.7  0-255 q8295.jpg
01:15:19  4.000  13.9  -9.7  -1.7  48.8  0-255 q8298.jpg m8298.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).