The US Navy brought back celestial navigation (with sextants) as a backup: * https://www.usni.org/magazines/proceedings/2021/december/bring-celestial-navigatio

The US Navy brought back celestial navigation (with sextants) as a backup: * https://www.usni.org/magazines/proceedings/2021/december/bring-celestial-navigation-21st-century https://www.usni.org/magazines/proceedings/2021/december/bri... * https://skyandtelescope.org/astronomy-news/u-s-navy-resumes-celestial-navigation-training-04042016/ https://skyandtelescope.org/astronomy-news/u-s-navy-resumes-...