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View Full Version here: : Amazing Airglow Above Las Campanas


Antu
11-03-2013, 12:40 PM
Hi All,

Sorry for being absent for a long time, too many things to do as usual. But yesterday I came across a quite impressive phenomenon. Well, we astrophotographers know very well how difficult sometimes to correct color gradients on our images. If the FOV of your telescope is small enough then it's much easier to do, however for really wide field instruments such postprocessing might become a hell. What is the cause of those color gradients ? For the answer, please have a look at the image I took yesterday at Las Campanas in Atacama desert:

http://spaceweather.com/gallery/full_image.php?image_name=Yuri-Beletsky-airglow_campanas_1362937190.jpg

Yes, this is atmospheric "airglow". Last night it was particularly strong. The airglow is the light of electronically and/or vibration-rotationally excited atoms and molecules 80 km or higher. The red color is due to OH radicals emission (and possibly atomic oxygen emission too). Unlike aurorae, which are visible in high latitudes only, airglow can be observable from anywhere on the planet. Basically, it does not depend on the latitude. Therefore, all of us are equally affected - regardless whether you are observing in Australia, Europe, or Chilean desert. Sigh ...

A low-resolution image is attached but the best would be to look at higher resolution (see the link above)

I used Canon 5D Mark II and Nikkor 14-24 f/2.8 lens.

Clear sky !

astroboy
11-03-2013, 02:31 PM
Amazing shot but why is it so distorted are you sure its the Nikkor 14 - 24 and not a Fish Eye ?

Octane
11-03-2013, 02:55 PM
That is superb!

Excellent work on the stitching, too.

H

colinmlegg
11-03-2013, 02:56 PM
Fantastic view! I wonder if the mountains have an influence on the structure and colour? Also have some shots from high in the Chilean Andes with similar structure and red. More vivid than I see in the deserts of Australia.

astroboy, I would guess a multiframe stitch.

gregbradley
11-03-2013, 05:34 PM
That's amazing.

Greg.

Antu
12-03-2013, 05:22 AM
Thanks, guys ! The Nikkor is not a fish-eye indeed, I took several exposures across the sky and then stitched them. Mountains actually do not have an influence on the structure and colour of airglow, because airglow forms at the altitude of ~80 km.

iceman
12-03-2013, 06:09 AM
Stunning Antu, thanks for posting and welcome back!

multiweb
12-03-2013, 07:55 AM
Very cool picture. :thumbsup: Does this airglow affect any of the research the big telescopes do?

Antu
22-03-2013, 10:59 PM
Thanks to all ! :)



Yes, it does a little.. However the effect is much smaller than the one from aurora (which is one of the main issues at south pole observational stations).

h0ughy
22-03-2013, 11:45 PM
wow not that is an eye opener

dvj
23-03-2013, 02:29 AM
:eyepop: Beautiful

prokyon
24-03-2013, 12:31 PM
Wonderful, I heard David Mailn talking about air glow some weeks ago. Your image is a perfect documentation.