2 ms·

Navies still train in using the sextant: * https://www.npr.org/2016/02/22/467210492/u-s-navy-brings-back-navigation-by-the-stars-for-officers https://www.npr.o

Navies still train in using the sextant: * https://www.npr.org/2016/02/22/467210492/u-s-navy-brings-back-navigation-by-the-stars-for-officers https://www.npr.org/2016/02/22/467210492/u-s-navy-brings-bac... * https://www.cbc.ca/news/canada/british-columbia/canadian-navy-sextant-1.3396636 https://www.cbc.ca/news/canada/british-columbia/canadian-nav... * https://en.wikipedia.org/wiki/Celestial_navigation https://en.wikipedia.org/wiki/Celestial_navigation Note that there are 'machines' (Nortronics NAS-14V2) that can look at the sky and return lat/long: * https://timeandnavigation.si.edu/multimedia-asset/nortronics-nas-14v2-astroinertial-navigation-system https://timeandnavigation.si.edu/multimedia-asset/nortronics... * https://maritime-executive.com/blog/automated-celestial-navigation-for-the-navy https://maritime-executive.com/blog/automated-celestial-navi...

eh_why_not 3y ago
For anyone else wondering: celestial navigation (by the stars) apparently works during the day as well, as the stars' infrared light remains "visible" [0]: > The new systems use infrared rather than visible light for locating stars, allowing daytime navigation. The stars shine just as brightly in the day sky as they do at night, but their light is masked by sunlight scattered by the atmosphere. The scattering is strongest at short wavelengths... But glimpse that same sky with a filter that allows only infrared light, and the sky suddenly becomes dark - and filled with stars. [0] https://www.popularmechanics.com/military/research/a36078957/celestial-navigation/ https://www.popularmechanics.com/military/research/a36078957...
- cosmojg 3y ago
  That's how ICBMs do it! > Intercontinental ballistic missiles use celestial navigation to check and correct their course (initially set using internal gyroscopes) while flying outside the Earth's atmosphere. The immunity to jamming signals is the main driver behind this seemingly archaic technique. Source: https://en.wikipedia.org/wiki/Celestial_navigation https://en.wikipedia.org/wiki/Celestial_navigation

eh_why_not 3y ago

For anyone else wondering: celestial navigation (by the stars) apparently works during the day as well, as the stars' infrared light remains "visible" [0]: > The new systems use infrared rather than visible light for locating stars, allowing daytime navigation. The stars shine just as brightly in the day sky as they do at night, but their light is masked by sunlight scattered by the atmosphere. The scattering is strongest at short wavelengths... But glimpse that same sky with a filter that allows only infrared light, and the sky suddenly becomes dark - and filled with stars. [0] https://www.popularmechanics.com/military/research/a36078957/celestial-navigation/ https://www.popularmechanics.com/military/research/a36078957...

cosmojg 3y ago
That's how ICBMs do it! > Intercontinental ballistic missiles use celestial navigation to check and correct their course (initially set using internal gyroscopes) while flying outside the Earth's atmosphere. The immunity to jamming signals is the main driver behind this seemingly archaic technique. Source: https://en.wikipedia.org/wiki/Celestial_navigation https://en.wikipedia.org/wiki/Celestial_navigation