NLC 2009-07-21/22
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 5 min
Date: 2009-07-21/22
UT forms bright height azimuth comments
ness top bot left rght e.g. weather
----- ----- ------ --- --- ---- ---- --------------------------------
21:15 X cloud to h 15 and top right
21:30 IV 2 25 330 20 cloud to h 5
21:45 IV 3 35 <325 >35 cloud to h 5
22:00 III,IV 4 >40 <325 >35 cloud to h 5
22:15 II,III 5 35 <325 >35 cloud on horizon
22:30 II,III 5 20 <325 25 cloud on horizon
22:45 III 5 cloud above and below
23:00 III 5 10 0 330 30 cloud below and in front
23:15 III 5 10 0 30 cloud below and in front
23:30 III 5 10 0 30 cloud on left below and in front
23:45 III 4 10 0 cloud on left below and in front
00:00 III 4 10 0 cloud on left, aeroplane trail
00:15 III 3 10 0 35 some cloud
00:30 III 3 10 0 <325 >35 some cloud
00:45 III 3 10 0 cloud above and some in front
01:00 NLC 3 10 behind cloud
01:15 NLC 3 behind cloud
01:30 III 3 10 behind cloud
01:45 I 4 behind cloud
02:00 I 4 15 behind cloud
02:15 II,III 4 20 cloud on left and below
02:30 NLC 3 through cloud gap
02:45 NLC? 1 through cloud gap
03:00 X cloud
03:15 X 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: 2009/07/21-22
Start: 21:30
End: 02:45
Forms: I,II,III,IV
Max elevation: >40
Max brightness: 5
Comments:
<a href="http://www.chiandh.me.uk/p/NLC_2009-07-21/22>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) ----- ------ ----- ----- ----- ----- ----- --------------------- 21:30 0.250 320.6 -5.8 2.7 169.1 0-255 q08556.jpg 21:45 0.800 323.9 -7.1 0.6 160.8 0-255 q08559.jpg 22:00 2.000 327.3 -8.3 -0.6 137.2 0-255 q08562.jpg 22:15 2.000 330.6 -9.4 -1.5 65.9 0-200 q08567.jpg 22:30 4.000 334.1 -10.3 -2.1 28.3 0-255 q08575.jpg 22:45 4.000 337.5 -11.2 -2.7 17.3 0-255 q08588.jpg 23:00 8.000 341.1 -12.0 -3.2 12.4 0-255 q08602.jpg 23:15 8.000 344.6 -12.6 -3.5 9.7 0-255 q08617.jpg 23:30 8.000 348.2 -13.1 -3.8 8.1 0-255 q08632.jpg 23:45 8.000 351.8 -13.4 -4.1 7.1 0-255 q08647.jpg 00:00 15.000 355.4 -13.7 -4.2 6.5 0-255 q08661.jpg 00:15 15.000 359.0 -13.8 -4.3 6.3 0-255 q08676.jpg 00:30 25.000 2.6 -13.8 -4.2 6.3 0-255 q08690.jpg 00:45 25.000 6.2 -13.6 -4.1 6.7 0-255 q08705.jpg 01:00 25.000 9.8 -13.3 -4.0 7.4 0-255 q08720.jpg 01:15 15.000 13.4 -12.9 -3.7 8.7 0-255 q08736.jpg 01:30 15.000 17.0 -12.3 -3.4 10.7 0-255 q08751.jpg 01:45 15.000 20.5 -11.7 -3.0 14.1 0-255 q08766.jpg 02:00 15.000 24.0 -10.9 -2.5 20.6 0-255 q08779.jpg 02:15 8.000 27.5 -10.0 -1.9 37.8 0-255 q08790.jpg 02:30 3.200 30.9 -8.9 -1.1 98.8 0-255 q08798.jpg 02:45 1.300 34.2 -7.8 -0.2 150.5 0-255 q08802.jpg m08802.jpg exp: Exposure time in seconds (200 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).
