
NLC 2009-07-20/21
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: 2009-07-20/21 UT forms bright height azimuth comments ness top bot left rght e.g. weather ----- ----- ------ ------- ---- ---- -------------------------------- 21:15 X cloud to h 15 and top left 21:30 X cloud 21:45 X cloud 22:00 X patchy cloud, probably no NLC 22:15 X patchy cloud, probably no NLC 22:30 0 cloud to h 5 22:45 0 cloud to h 5 23:00 0 cloud to h 5 23:15 0 cloud to h 5, and above h 20 23:30 0 cloud to h 5, some patches above 23:45 X cloud, probably no NLC 00:00 X cloud 00:15 X cloud 00:30 NLC? 1 5 350 10 patchy cloud 00:45 NLC 1 5 350 10 patchy cloud 01:00 NLC 1 5 350 10 patchy cloud 01:15 X cloud above h 5 01:30 X cloud above h 5 01:45 X cloud 02:00 X cloud 02:15 X cloud 02:30 X cloud 02:45 X cloud to h 20 03:00 X cloud to h 15 03:15 X cloud to h 10 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: 2009/07/20-21 Start: 00:30 End: 01:00 Forms: NLC Max elevation: 5 Max brightness: 1 Comments: <a href="http://www.chiandh.me.uk/p/NLC_2009-07-20/21>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) ----- ------ ----- ----- ----- ----- ----- --------------------- 00:30 25.000 2.6 -13.6 -4.1 6.8 0-255 q08433.jpg m08433.jpg 00:45 25.000 6.2 -13.4 -4.0 7.2 0-255 q08448.jpg m08448.jpg 01:00 25.000 9.8 -13.1 -3.9 8.0 0-255 q08463.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).