Astrarium

Set the place and the time, and see that sky. Everything runs on the device, so it all works where there is no signal.

Choose a place and a time, and Astrarium draws that sky. Every position is computed on the device, so the whole app works where there is no signal.

CATALOGUES (all bundled) • 9,096 stars — Yale Bright Star Catalogue, to about magnitude 8: everything the naked eye can see • 155 nebulae, clusters and galaxies — the Messier and Caldwell objects, with photographs and descriptions • The 88 IAU constellations: 672 line segments and the classical figures • The Milky Way, built from the integrated light of the Tycho-2 stars • Planets and the Moon from JPL DE421, with surface maps, libration, lunar age and the traditional full-moon names • 16 major meteor showers, the MPC observatory codes, observing sites worldwide

WHAT IT DOES • Whole-sky and horizon views, pinch zoom down to a one-arcminute field • Jump to any date, run the clock at up to 6000x, step by the synodic month • Planet close-ups: apparent diameter, phase, geocentric and heliocentric distance, orbital elements, and the moons of Jupiter, Saturn and Mars — tap one for its own figures • Meteor shower calendar: maximum in local time and UT, radiant altitude, moon conditions, and an expected hourly rate from the ZHR and the radiant altitude • Satellites: fetch CelesTrak elements and watch the ISS or Tiangong cross the chart, with visible-pass predictions • Comets and asteroids from the MPC and JPL, plotted on the chart • Four coordinate grids, the ecliptic, celestial equator, galactic plane and meridian, and field-of-view frames for smart telescopes and camera lenses • Switch each layer on its own: constellation lines and names, stars, star names, the Sun and planets, deep-sky objects, the Milky Way and the constellation figures — turn the stars off and the figures stand alone • Limiting magnitude that follows twilight and moonlight, a red night-vision mode, PNG/PDF export, a captioned demo, screen recording, and spoken summaries

LOCATION Your position is used only to compute the sky where you are, and never leaves the device. If you decline, pick a site from the list or type in the coordinates: nothing is lost.

No ads, no in-app purchases, no account. Every source and licence is listed in the app under Credits.