NLC 2012-06-28/29

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 dSLR with limited field of view A ~325-35, h ~0-40
          images every 15 min
Date: 2012-06-28/29

  UT   forms  bright   height   azimuth   comments
               ness   top bot  left rght  e.g. weather
-----  -----  ------  --- ---  ---- ----  --------------------------------
21:45  X                                  widespread cloud
22:00  X                                  widespread cloud
22:15  0                                  some cloud patches
22:30  0
22:45  II         1    10   8    20   30
23:00  I          1    18      <325    5
23:15  I          1    20   5  <325   30
23:30  I          2    17      <325   30  cloud to h 10
23:45  I          2    17      <325       cloud to h 10 or 15
00:00  I          3    14      <325  >35  cloud to h 10
00:15  I          3    12                 through cloud
00:30  I          3    15            >35  through cloud
00:45  I          3                       through cloud
01:00  NLC        3                       through cloud
01:15  NLC        2                       through cloud
01:30  X                                  widespread cloud
01:45  I,IV       2                       through cloud
02:00  IV         1                       through cloud
02:15  X                                  widespread cloud
02:30  X                                  widespread cloud
02:45  X                                  widespread cloud

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: 2012/06/28-29
Start: 22:45
End: 02:00
Forms: I,II,IV
Max elevation: 20
Max brightness: 3
Comments:
<a href="http://www.chiandh.me.uk/p/NLC_2012-06-28/29">Images</a>.

forms: I: veil
       II: bands
       III: waves
       IV: whirls
       O: 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)
----- ------ ----- ----- ----- -----  ----- ---------------------
22:45  0.600 338.9  -8.5  -0.8 126.8  0-255 q00322.jpg m00322.jpg
23:00  1.000 342.3  -9.2  -1.3  76.9  0-255 q00324.jpg m00324.jpg
23:15  2.000 345.8  -9.8  -1.8  43.6  0-255 q00327.jpg m00327.jpg
23:30  2.500 349.2 -10.3  -2.1  30.3  0-255 q00330.jpg
23:45  3.200 352.7 -10.6  -2.3  24.4  0-255 q00334.jpg
00:00  4.000 356.2 -10.8  -2.4  21.6  0-255 q00338.jpg
00:15  4.000 359.7 -10.9  -2.5  20.7  0-255 q00342.jpg
00:30  4.000   3.2 -10.8  -2.5  21.3  0-255 q00346.jpg
00:45  4.000   6.7 -10.6  -2.3  23.7  0-255 q00350.jpg
01:00  3.200  10.2 -10.3  -2.1  28.9  0-255 q00354.jpg
01:15  2.000  13.7  -9.9  -1.8  40.4  0-255 q00357.jpg
01:45  0.600  20.6  -8.6  -0.9 119.6  0-255 q00361.jpg
02:00  0.400  23.9  -7.9  -0.2 149.7  0-255 q00363.jpg m00363.jpg

exp: Exposure time in seconds (400 ISO, f/3.5).
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).