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Heliosynchronous satellites enter a darkness region at high latitude in winter. They are most of the time programmed not the capture an image when the solar zenith angle becomes too large because the quality of the signal is then lower.

My question is : what is the maximum solar zenith angle for the acquisition of Landsat-8 images ? This would help me compute the maximum latitude covered in winter. I would like to compare with Sentinel-2, which I found is 84.5° max SZA.

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    This is not my field but according to USGS, a solar zenith angle > 76 degrees is considered undesirable and the surface reflectance is no longer processed. – Joseph Apr 29 '16 at 10:49
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    It depends what you are looking at. If you look at the snow, you can use images with relatively large SZA (MOD 10 snow cover from MODIS uses up to 86.5 ° for example) Furthermore, I believe that atmospheric correction has improved and specific bands are now onboard to help ,so you can now extract information at high latitude. – radouxju Apr 29 '16 at 10:54
  • 76° degree is very restrictive if you consider the satellite overpass time around 10.30 AM. It would (very roughly) mean no image above Boston, Shenyang or Rome in december – radouxju Apr 29 '16 at 11:01
  • That's quite interesting, thank you for the descriptions. I've read a few Landsat-related questions here but unfortunately, haven't worked with them (yet). – Joseph Apr 29 '16 at 11:05
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After having reviewed the metadata from every Landsat 8 scene acquired from launch to mid March 2016, I've found that the lowest sun elevation angle consistently present in the archive is around 5.5, giving you a 84.5° SZA.

Below is a histogram of the sun elevation angles of the reviewed Landsat 8 scenes.

Histogram of sun elevation angles present in the Landsat archive

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    this was a great idea to find out the answer. Are you aware of any technical document that confirms it ? – radouxju Apr 29 '16 at 11:16
  • @radouxju can't say that I am. I don't think that the USGS have provided that information in any of their technical documents, but you could write them an email asking them. They usually respond pretty quickly and thoroughly. – Mikkel Lydholm Rasmussen Apr 29 '16 at 11:28

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