Antikythera Mechanism Dial

In 1901, divers raised corroded lumps of bronze from an ancient shipwreck off the Greek island of Antikythera. They were the remains of the Antikythera mechanism, built in the 2nd or 1st century BC: the oldest known geared computer, an astronomical calculator that showed the positions of the Sun and the Moon, the phase of the Moon and, according to its inscriptions, the planets, and that predicted eclipses. Its fragments are kept at the National Archaeological Museum in Athens. This app brings its front dial back to life, after the reconstruction by Freeth et al. (University College London, 2021), and computes it exactly as its gears did. TURN THE CRANK The Sun, the Moon with its phase, Mercury, Venus, Mars, Jupiter and Saturn move around the zodiac ring. On Apple Watch the Digital Crown is the crank; on iPhone a wheel runs through hours, days, lunar months and years. TAP A CELESTIAL BODY Each card gives the sign, the position, the motion and, for the Moon, the phase, the lit fraction and the age. THE NEXT ECLIPSE ACCORDING TO THE MACHINE A countdown to the next eclipse predicted by the machine, with the Saros dial's announcement, compared with the real eclipse when it is known. THE MECHANISM REVEALED (iPhone, iOS 18 or later) Lift the bronze plate: the wheels of the reconstructed mechanism turn with the pointers. Fast playback, back view, exploded view, and the status of each part: surviving, reconstructed or hypothetical. THE REAL SKY (iPhone with iOS 18 or later, and Apple Watch with a compass) Raise your iPhone: with the compass and the motion sensors, each pointer aims at the real Sun, Moon and planets. Switch between "Sky" and "Machine" to see how far the ancient machine drifts from the sky. Direction depends on the compass (about 5 to 15°). Your location never leaves the device; without it, pick a city. On an Apple Watch with a compass (Series 5 or later, SE, Ultra), the same mode is in Settings. ON APPLE WATCH A full-screen app with its patinated bronze dial, a quiet Always On display, and complications for your watch faces (mini dial, Sun and Moon, planets, next eclipse) plus a Smart Stack widget. The app is not a watch face: watchOS does not allow third-party watch faces. ON iPHONE Widgets for the Home Screen, the Lock Screen and StandBy, and a black bedside mode with a red night palette. In nine languages, with the zodiac and Egyptian month inscriptions in your language or in ancient Greek. No account, no ads, no network connection, no data collected. Antikythera mechanism reconstruction by taciclei (CC BY 4.0); after T. Freeth et al., Scientific Reports 11, 5821 (2021). WMM2025 magnetic model (NOAA, BGS).