chi and h site logo

NLC 2015-07-15/16

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: 2015-07-15/16

   UT     forms  bright   height   azimuth   comments
                  ness   top bot  left rght  e.g. weather
--------  -----  ------  --- ---  ---- ----  --------------------------------
21:30:01  0                                  some cloud
21:45:01  0                                  some cloud
22:00:06  0                                  some cloud
22:15:03  0                                  some cloud
22:30:10  IV         3    10         5   35  through cloud
22:45:18  II,IV      3    12       355  >35  through cloud
23:00:32  II         3                       through cloud
23:15:33  I          2                       through cloud
23:30:53  X                                  almost overcast
23:45:53  X                                  almost overcast
00:00:47  X                                  widespread cloud
00:15:47  X                                  widespread cloud
00:30:47  X                                  cloud to h 15
00:45:47  X                                  cloud to h 15
01:00:53  X                                  cloud to h 15
01:15:53  I,II       3    12                 through cloud
01:30:32  I          3    14                 through cloud
01:45:32  I          3    15                 cloud to h 5
02:00:09  I          2     8                 through cloud
02:15:09  X                                  patchy cloud to h 10
02:30:06  X                                  patchy cloud to h 15
02:45:01  0                                  patchy cloud to h 10
03:00:05  X                                  haze and some cloud
03:15:01  X                                  cirrus

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: 2015/07/15-16
Start: 22:30
End: 02:00
Forms: I,II,IV
Max elevation: 15
Max brightness: 3
Comments: Cloud 23:30-01:00.
http://www.chiandh.eu/nlccam/20150715-16.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)
-------- ------ ----- ----- ----- -----  ----- -------------------
22:30:10  2.000 334.5  -9.3  -1.4  73.1  0-255 q4558.jpg
22:45:18  4.000 338.0 -10.1  -2.0  33.3  0-255 q4562.jpg
23:00:32  8.000 341.5 -10.9  -2.5  20.7  0-255 q4567.jpg
23:15:33  8.000 345.0 -11.5  -2.9  15.3  0-255 q4572.jpg
01:15:53 15.000  13.6 -11.7  -3.0  13.9  0-255 q4620.jpg
01:30:32  8.000  17.0 -11.2  -2.7  17.8  0-255 q4625.jpg
01:45:32  8.000  20.5 -10.5  -2.2  25.9  0-255 q4630.jpg
02:00:09  2.000  23.8  -9.7  -1.7  47.1  0-180 q4632.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).