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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   Hum… 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
- - scalbers   Here is a more direct link to the recent paper tha...   May 12 2015, 06:59 PM
- - Deimos   Yes, I was a bit annoyed by that APOD comment. The...   May 14 2015, 02:39 AM
- - scalbers   Here's a simulation with my latest software fo...   Sep 19 2016, 06:28 PM
- - neo56   Amazing work Scalbers, that's a really nice pr...   Sep 28 2016, 05:12 PM
- - scalbers   Thanks Thomas, and glad they can be used in your m...   Oct 2 2016, 03:13 PM
- - scalbers   Greetings, Considering that light can reflect off...   Oct 30 2016, 08:27 PM
- - scalbers   I can report on some progress with a Monte Carlo p...   Jan 28 2018, 09:46 PM
- - fredk   I'm curious what are the differences between t...   Jan 28 2018, 10:18 PM
|- - scalbers   Indeed both techniques involve tracing of light ra...   Jan 29 2018, 01:09 AM
- - antipode   If you looked up on an average dusty day in Gale C...   Jan 29 2018, 02:04 AM
- - djellison   Do you mean at night? If so - yes - https://www.j...   Jan 29 2018, 09:28 PM
|- - mcaplinger   QUOTE (djellison @ Jan 29 2018, 01:28 PM)...   Jan 29 2018, 09:56 PM
- - elakdawalla   Would Jupiter be visible to the naked eye in the d...   Jan 29 2018, 11:46 PM
- - Explorer1   A quick Google search shows that some folks have s...   Jan 30 2018, 12:02 AM
- - scalbers   I've seen Jupiter at 10:20am from a high deser...   Jan 30 2018, 12:50 AM
|- - Explorer1   QUOTE (scalbers @ Jan 29 2018, 07:50 PM) ...   Jan 30 2018, 01:17 AM
- - antipode   Hi all, OP here (at least in terms of Mars' sk...   Jan 30 2018, 05:34 AM
|- - scalbers   QUOTE (antipode @ Jan 30 2018, 05:34 AM) ...   Jan 30 2018, 02:36 PM
- - ngunn   I seem to recall one of the rovers acquired at lea...   Jan 30 2018, 09:57 AM
|- - mcaplinger   QUOTE (ngunn @ Jan 30 2018, 01:57 AM) I s...   Jan 30 2018, 03:55 PM
- - scalbers   Olympus Mons should be pretty good as I'm gett...   Jan 30 2018, 04:45 PM
|- - JRehling   I'm not sure how much the martian sky varies, ...   Jan 30 2018, 07:29 PM
|- - mcaplinger   QUOTE (JRehling @ Jan 30 2018, 11:29 AM) ...   Jan 30 2018, 08:22 PM
|- - fredk   QUOTE (mcaplinger @ Jan 30 2018, 09:22 PM...   Jan 31 2018, 12:20 AM
|- - JRehling   Great shot of Phobos, mcaplinger! (I assume th...   Jan 31 2018, 04:27 PM
- - Ant103   Actually, there was a Mastcam mosaic of the sky, n...   Jan 30 2018, 11:33 PM
|- - scalbers   QUOTE (Ant103 @ Jan 30 2018, 11:33 PM) Ac...   Jan 31 2018, 07:39 PM
|- - vikingmars   QUOTE (Ant103 @ Jan 31 2018, 12:33 AM) Ac...   Jan 31 2018, 08:29 PM
|- - mcaplinger   QUOTE (Ant103 @ Jan 30 2018, 03:33 PM) Ac...   Jan 31 2018, 09:11 PM
- - Deimos   Navcam images of Phobos just before & after su...   Jan 31 2018, 11:35 PM
- - scalbers   Indeed it's kind of similar to this earlier si...   Feb 1 2018, 12:33 AM
- - scalbers   Here is an attempt to generate a similar polar (fi...   Feb 4 2018, 12:54 AM
- - Sean   This is wonderful work Steve.... can you please ch...   Mar 31 2018, 12:19 AM
- - scalbers   Hi Sean - thanks. Good question - the intent (as b...   Mar 31 2018, 12:27 AM
- - JohnVV   normally i use the gui for the vips image lib ...   Apr 2 2018, 04:24 AM
- - scalbers   Thanks JohnVV. Revisiting this a bit I made a sequ...   Sep 4 2021, 06:31 PM
- - scalbers   Relating to the last linked paper above, I was abl...   Dec 5 2021, 09:19 PM
- - scalbers   After looking at some additional papers and doing ...   Dec 27 2021, 06:21 PM
- - scalbers   Thanks to Damia's post in a different thread (...   Jan 23 2022, 09:09 PM
|- - fredk   QUOTE (scalbers @ Jan 23 2022, 10:09 PM) ...   Jan 23 2022, 10:37 PM
- - scalbers   QUOTE (fredk @ Jan 23 2022, 10:37 PM) Can...   Jan 23 2022, 11:29 PM
- - Deimos   The Sun was saturated in the recent M2020 sunset i...   Jan 24 2022, 12:02 AM
- - Deimos   Holy Moly! That Applied Optics paper modeled t...   Jan 24 2022, 12:19 AM
- - scalbers   Yes we could still provide the authors with that d...   Jan 24 2022, 12:31 AM
- - scalbers   Here's a animated version with -0.15 Angstrom ...   Feb 6 2022, 07:44 PM
- - fredk   This MSL navcam image: https://mars.nasa.gov/msl-...   Sep 15 2022, 10:32 PM
- - climber   Any chance it could be zodiacal light instead ?   Sep 16 2022, 06:26 AM
|- - djellison   QUOTE (climber @ Sep 15 2022, 10:26 PM) A...   Sep 16 2022, 02:21 PM
- - nprev   Likely has at least something to do with the scale...   Sep 16 2022, 08:04 AM
- - scalbers   As mentioned a longer twilight on Mars relates to ...   Sep 16 2022, 04:34 PM
- - Bill Harris   "Do we expect martian twilight to last longer...   Sep 19 2022, 03:25 AM
- - scalbers   Earth sky analogy to Mars: https://www.scmp.com/n...   Apr 10 2023, 06:32 PM
- - scalbers   For convenience is there a handy reference to find...   Jul 2 2023, 09:50 PM
|- - rlorenz   QUOTE (scalbers @ Jul 2 2023, 05:50 PM) F...   Jul 4 2023, 04:03 PM
- - fredk   The filename sites for MER and MSL are still up: ...   Jul 2 2023, 11:26 PM
- - mcaplinger   https://www.giss.nasa.gov/tools/mars24/   Jul 2 2023, 11:43 PM


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