
NLC 2011-07-26/27
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: 2011-07-26/27 UT forms bright height azimuth comments ness top bot left rght e.g. weather ----- ----- ------ --- --- ---- ---- -------------------------------- 21:15 0 21:30 0 21:45 0 22:00 0 22:15 NLC 1 3 10 20 22:30 NLC 2 3 5 20 22:45 NLC 1 4 5 20 through haze 23:00 0 23:15 NLC 1 2 2 15 through cloud 23:30 NLC 2 3 355 20 through haze 23:45 NLC? 1 3 353 12 through haze 00:00 X cloud on right to h 8 00:15 X cloud to h 20 00:30 X cloud to h 30 00:45 X cloud to h 30 01:00 X widespread cloud 01:15 X widespread cloud 01:30 X almost overcast 01:45 X widespread cloud 02:00 X cloud to h 20 02:15 X cloud to h 15 02:30 X cloud to h 15 02:45 0 cloud to h 15 03:00 0 cloud to h 10 03:15 X widespread cloud 03:30 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: 2011/07/26-27 Start: 22:15 End: 23:45 Forms: NLC Max elevation: 4 Max brightness: 2 Comments: Through haze. <a href="http://www.chiandh.me.uk/p/NLC_2011-07-26/27">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) ----- ------ ----- ----- ----- ----- ----- --------------------- 22:15 3.200 330.3 -10.3 -2.1 29.8 0-255 q16974.jpg m16974.jpg 22:30 6.000 333.8 -11.3 -2.7 16.9 0-255 q16979.jpg 22:45 13.000 337.3 -12.1 -3.3 11.6 0-255 q16985.jpg m16985.jpg 23:15 15.000 344.4 -13.5 -4.1 6.9 0-255 q16997.jpg m16997.jpg 23:30 15.000 348.0 -14.0 -4.4 5.7 0-255 q17003.jpg m17003.jpg 23:45 15.000 351.7 -14.4 -4.6 5.0 0-255 q17009.jpg m17009.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).