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A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Frank Reed
Date: 2018 May 18, 12:08 -0700
I wrote a few minutes ago:
"I believe that's a staged photo in a simulator, right? Whatever sextant they're planning to use in these experiments is scheduled to launch on a cargo flight now scheduled for this Monday, May 21."
Just a little confirmation on that. The guy in the photo is German (ESA) astronaut Alex Gerst. He was aboard the ISS for six months in 2014 (when he surely did not have the sextant --else we would have seen photos already!), and he is scheduled to launch to the station again on June 6 of this year. So yes, definitely a simulator photo. The fact that he was training with this instrument does suggest strongly that the sextant being launched on Monday will be a standard COTS (commercial off-the-shelf) marine sextant --quite possibly a Celestaire Astra IIIB.
Frank Reed