Rosliston Astronomy Group


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Peter Hill

Iridium Flare & ISS


Yes it was beautifully clear on Friday night, but it was too windy, thought I'd be sheltered in the garden but no, any gust set the image in the eyepiece jigging about!!! Forecast looks good for Christmas eve and hopefully not too windy.
However all was not lost and took the opportunity to orientate myself with the binoculars and practised locating the favourites like Andromeda, the double cluster, M44 etc as well as viewing the plaiedes, hyades, and the joys of orion.
The evening had started very promisingly with a pass of the ISS and a -8 mag Iridium flare  forecast by
ISS rising in west at 16:42 and setting in east at 16:51, at max altitude at 16:47:52 max brightness -3.0
First image shows ISS at its zenith, passing between Matar and Scheat in Pegasus and travelling parallel to Scheat and Alpheratz in Pegasus. Canon 450D Canon 15mm Fisheye Lens ISO 400, F10, 50" , cable release on tripod.
Second image is ISS setting in east, with  Aries ( Hamal & Sheratan) , near top r of centre , Atik in Perseus to left and Aldebaran just showing to the left of trees at bottom. same set up 39" exposure. Both images in Raw and processed in photoshop.
Video is best viewed at a half screen max, or slightly less, shows ISS emerging from sky glow in West , rising to Zenith and then travelling across sky to sink in west through the branches.
just after the ISS had passed, Iridium 96 was due to pass overhead on a S to N path flaring as it passed through Cassiopeia at an altitude of 66 deg.
First image shows whole sky view and gives perspective to flare. Canon 450D Canon15mmfisheye lens, ISO 400, F10, 35" exposure , remote cable release on tripod. (RAW)
Second image is close up section from image 1 showing brightening trail to max of -8 , an position in Cassiopeia. Path of satellite S - N  is R to left on images.
All image processing, cropping in P.S.6
Video clip shows what you would have seen if looking at Cassiopeia naked eye, image is near top of screen. Used same camera as for ISS, Canon LegriaFS406, wide view, manual focus to infinity, AWB, mounted on tripod.
Have also attached details Flare info from heavensabove  site.
The ISS is visible because of the sunlight reflected from its massive solar panel array, the Iridium flares are caused by reflection of sunlight from their very large antenna , see diagram.
Rumour has it there might be something flashing across the night skies on wed night , flashing and making noise !!

Pete H


Flare details (.doc file)
Iridium Flare movie 16/54/30(UT) 19 December 2014 (-8) (WMV movie file)
ISS Pass information (.doc file)
ISS movie 16.42.29 19 December 2014 (WMV movie file)

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