NotAstray is a telescope guide and star map for your phone. Attach the phone to the tube, pick a star, planet, galaxy or nebula and follow the arrows until it's in the eyepiece. It turns any telescope into a push-to telescope, from a simple Dobsonian to a computerised GoTo mount, like digital setting circles with no extra electronics.

If your phone's camera can see the sky, NotAstray photographs the stars and works out exactly where the telescope is pointing (plate solving). No alignment stars to set up, and nothing to redo when the compass drifts.

Made for beginners in astronomy and experienced observers alike: it tells you what your telescope can really show under your sky tonight, plans your night of stargazing and keeps a log of what you've seen. Works offline. Available in English and Polish.

FINDING TARGETS

• Push-to guidance: a path on the star map and two arrows show which way to move. The phone tells you when you're on target.
• Star map: stars, deep-sky objects, planets, comets, constellations and the Milky Way.
• Search: stars, double stars, Messier, NGC and IC objects, planets, comets, the Moon and the Sun.
• Object details: what the eyepiece shows now, when to look and a short description.
• Visibility prediction: whether your telescope will show an object under your sky, and with which eyepiece.
• Comets: orbits from the IAU Minor Planet Center, ready to guide or slew to.
• Audio guidance: spoken directions keep your eyes off the screen.
• Sun safety: a warning before guiding or slewing near the Sun.

SETUP AND CAMERA

• Quick setup: align on 2–3 stars, or skip star alignment with a camera setup.
• Camera plate solving: the phone photographs the sky, directly or through a finder, and keeps the pointing exact.
• Tune camera: the app learns how your phone's camera behaves, so plate solving gets more reliable and faster.
• USB camera: plate solve through a small USB (UVC) camera mounted next to the phone.
• Equipment profiles: one per telescope, switched in one tap.

TELESCOPE CONTROL

• GoTo: LX200/OnStep, Celestron NexStar or Sky-Watcher mounts over Wi-Fi, Bluetooth or USB.
• Camera-checked GoTo: after a slew, the camera checks where the mount stopped and recentres the target.
• Hand controller: on-screen arrows or a floating joystick.

OBSERVING

• Night planner (full version): the best objects for tonight, in the order that suits you.
• Live stack (full version): faint galaxies and nebulae build up on the screen, in colour where the camera allows. Save the picture or a 16-bit file.
• Companion phone (full version): a second phone in your hand shows the map and moves the mount, over Wi-Fi or Bluetooth.
• Planetarium apps (full version): use NotAstray as a telescope in SkySafari, Stellarium, Cartes du Ciel or N.I.N.A. over LX200 or ASCOM Alpaca.
• Observing log: every object you visit, with the date, time and sky conditions. No typing needed.
• Sky quality (experimental): how dark and clear your sky is, night after night.
• Dew and focus monitor (experimental): catches dew or focus drift during the night.
• Night mode: red on black, to keep your eyes adapted to the dark.

OFFLINE AND PRIVATE

No account, no ads, no tracking. Everything works without a signal. The app goes online only to download comet orbits or send a problem report, when you ask.

FREE AND FULL VERSION

Free: guiding with the phone's sensors, telescope control and plate solving on 3 targets or for 30 minutes each night, whichever comes first.

Full version, a one-time purchase: unlimited plate solving, plus the night planner, live stack, companion phone and planetarium apps.

NotAstray is not affiliated with or endorsed by Celestron, Sky-Watcher, Meade, OnStep, SkySafari, Stellarium, Cartes du Ciel, N.I.N.A., the ASCOM Initiative or the IAU Minor Planet Center. All trademarks belong to their owners.