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The Martian Sky
Bjorn Jonsson
post Oct 11 2009, 06:41 PM
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I have been attempting to make computer generated images of the Martian atmosphere, both as seen from the surface and from space. To check the results I have been looking for spacecraft images to use as ground truth. I have found lots of images - by far the best ones I have found are from UMSF in this thread: http://www.unmannedspaceflight.com/index.php?showtopic=3324

However, I'm always looking for more ;-). So if anyone knows of more and/or better images I'm interested in them. What would be best are mosaics showing the sky from the horizon (with the horizon/surface visible) and towards the zenith.

The sky varies a lot because of variable amount of dust but the general impression I get is that the sky is bright near the horizon (usually brighter than the surface) but gets much darker higher in the sky. There is probably a fairly large, bright area in the sky near the sun, possibly less reddish (lower R/B ratio) than parts of the sky farther from the sun.

I'm already getting fairly interesting results, this one has a field of view of 90 degrees:

Attached Image

(needless to say this one is 'overexposed' near the horizon; dynamic range is sometimes a problem)

The problem is that even though this may not be bad the limb currently appears far too bright as seen from space :

Attached Image


This shows that my atmospheric model is erroneous in some way - I suspect that as seen from the surface the Martian sky is darker high above the horizon than I have been assuming.
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Posts in this topic
- Bjorn Jonsson   The Martian Sky   Oct 11 2009, 06:41 PM
- - djellison   That first image is surprisingly (and pleasingly) ...   Oct 11 2009, 07:29 PM
- - ngunn   I expect you've seen this paper (one of my fav...   Oct 11 2009, 09:24 PM
- - Ant103   The first image seems very good for me. Don't ...   Oct 13 2009, 08:42 AM
|- - djellison   QUOTE (Ant103 @ Oct 13 2009, 09:42 AM) wi...   Oct 13 2009, 05:15 PM
- - mcaplinger   QUOTE (Bjorn Jonsson @ Oct 11 2009, 10:41...   Oct 13 2009, 04:48 PM
|- - Bjorn Jonsson   QUOTE (mcaplinger @ Oct 13 2009, 04:48 PM...   Oct 14 2009, 12:49 AM
|- - mwolff   QUOTE (Bjorn Jonsson @ Oct 13 2009, 06:49...   Oct 15 2009, 03:32 PM
- - vikingmars   ...And here is a photo controlled mosaic showing t...   Oct 14 2009, 10:43 PM
- - djellison   All those words and 'sky hemisphere' didn...   Oct 15 2009, 10:12 PM
- - ngunn   Sorry - who's Mike? - and who mentioned 's...   Oct 15 2009, 10:39 PM
- - djellison   Check the bottom of http://pancam.astro.cornell.ed...   Oct 16 2009, 05:59 AM
- - ngunn   Much appreciated, thanks Doug. I'll start agit...   Oct 16 2009, 07:38 AM
- - DDAVIS   I wish they would place a hemispherical mirror som...   Oct 16 2009, 07:53 PM
- - Ant103   Humů I will better prefer a camera with a fisheye ...   Oct 16 2009, 08:26 PM
|- - DDAVIS   So would I, but the mirror should be easier to arr...   Oct 16 2009, 11:01 PM
- - djellison   It would also be a lot lighter. Beagle 2 used a w...   Oct 17 2009, 08:41 AM
- - Ant103   Here is the settings of the atmosphere in TG2, set...   Oct 17 2009, 11:32 AM
|- - Bjorn Jonsson   QUOTE (Ant103 @ Oct 17 2009, 11:32 AM) He...   Oct 19 2009, 12:58 AM
|- - vikingmars   Bjorn, your test images and simulations are really...   Oct 20 2009, 07:47 AM
|- - mwolff   QUOTE (Bjorn Jonsson @ Oct 18 2009, 07:58...   Oct 20 2009, 04:53 PM
|- - Bjorn Jonsson   QUOTE (mwolff @ Oct 20 2009, 04:53 PM) I ...   Oct 21 2009, 05:39 PM
|- - Bjorn Jonsson   I have now made significant improvements to my ren...   Dec 1 2009, 12:33 AM
|- - vikingmars   Really interesting Bjorn ! My 1st impression i...   Dec 1 2009, 07:11 PM
||- - Bjorn Jonsson   Which reminds me - there really should be a test r...   Dec 1 2009, 11:49 PM
|- - Bjorn Jonsson   QUOTE (Bjorn Jonsson @ Dec 1 2009, 12:33 ...   Dec 22 2009, 11:31 PM
- - tolis   One question that is relevant to the appearance of...   Oct 21 2009, 01:09 PM
|- - vikingmars   QUOTE (tolis @ Oct 21 2009, 03:09 PM) One...   Oct 21 2009, 01:37 PM
- - djellison   Don't encourage him Bjorn   Dec 2 2009, 08:15 AM
- - DDAVIS   I would like to encourage a small hemispheric mirr...   Dec 2 2009, 08:04 PM
- - James Sorenson   I have imagined a modified MER hazcam camera, but ...   Dec 2 2009, 09:17 PM
- - hendric   Don, Some experiments and deconvolution software...   Dec 2 2009, 10:44 PM
- - mcaplinger   An all-sky pan with the 34mm Mastcam on MSL wouldn...   Dec 2 2009, 11:55 PM
|- - mwolff   --- unnecessary quoting removed --- That would be...   Dec 3 2009, 03:13 PM
- - scalbers   Nice animation above by Bjorn from 2009. Here...   Jan 26 2014, 11:06 PM


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