
NLC 2017-08-03/04
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: 2017-08-03/04 UT forms bright height azimuth comments ness top bot left rght e.g. weather -------- ----- ------ --- --- ---- ---- -------------------------------- 20:45:04 0 few cloud patches 21:00:05 X some patchy cloud 21:15:06 0 clear 21:30:09 0 clear 21:45:18 0 patchy cloud to h 5 or 15 22:00:32 0 patchy cloud to h 5 22:16:31 X patchy cloud to h 10 22:31:25 X patchy cloud 22:46:24 X patchy cloud 23:01:24 X widespread cloud 23:16:24 X almost overcast 23:31:24 X overcast 23:46:25 X almost overcast 01:01:24 X almost overcast 01:16:24 X almost overcast 01:31:24 X almost overcast 01:45:46 II 3 through cloud 02:00:26 II 3 through cloud, laser beams 02:16:24 X almost overcast 02:30:53 X almost overcast 02:45:32 X almost overcast 03:00:18 X almost overcast 03:15:08 X almost overcast 03:30:05 X almost overcast 03:45:05 X almost 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: 2017/08/03-04 Start: 01:45 End: 02:00 Forms: II Max elevation: Max brightness: 3 Comments: Through cloud. http://www.chiandh.eu/nlccam/20170803-04.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) -------- ------ ----- ----- ----- ----- ----- ------------------- 01:45:46 15.000 21.4 -14.6 -4.7 4.6 0-255 q5135.jpg 02:00:26 8.000 24.9 -13.8 -4.3 6.2 0-255 q5140.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).