A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: Paul Dolkas
Date: 2018 May 18, 10:43 -0700
Aparently NASA is launcing a sextant to the ISS as part of an experiment to develop tecniques for back-up navigation, should the primary systems fail. This isn't the first time they have done this - sextants were flown on Geminis 10, 12, and Skylab. On Gemini 12, in fact, Buzz Aldrin used a sextant during a rondezvous with an Agena rocket when the Gemini's radar failed.
The picture shows Alex Gerst using a conventional marine sextant in the ISS Cupola. The aforementioned flights used devices specially designed for spaceflight. (I have info if anybody is interested in having it posted)
The clip is from Space.com, BTW - Paul