The Cosmos on Your Wrist
(IMPORTANT: This is the standalone StarHalo™ 2 app and complication data source. To use it as a watchface, also download and install the free StarHalo™ 2 watchface — the Wear 5+ container that hosts the StarHalo™ 2 complication and presents it as a full watchface.)
From the developer of SkyHalo™ 2 Weather, StarHalo™ 2 is a real-time astronomical companion for Wear OS — built for professional and amateur astronomers who want accurate sky data at a glance, whether at the telescope, in the field, or planning the next session.
Even if you're not an astronomer and never use any of its astronomical features, StarHalo™ is one of the most beautiful watch faces available for Wear OS.
New in the Transient Events upgrade: aurora forecasts and alerts (Kp-based alerts for your latitude), meteor shower peak alerts with a configurable lead time, and local solar and lunar eclipse circumstances — including contact times for the next eclipse visible from your location.
StarHalo™ 2 centers on a dynamically generated planisphere keyed to your location and time. At a glance you see the Moon, Sun, planets, stars, constellation figures, Messier objects, and the Milky Way — day or night — with optional real-time daylight and twilight tinting that tracks sunrise, sunset, and astronomical twilight.
Observational tools:
— Sky map: Azimuthal equidistant projection from horizon to zenith, with meridian elevation marks and cardinal directions. Rotate the sky view by tapping the edges to reduce distortion near the horizon and bring targets toward the center. Double-tap any point for a magnified field (~30° / ~6×) showing Moon, Sun, planets, comets, and Messier objects in that region — useful for conjunctions and crowded fields.
— The Moon: Live disk, phase, and orientation in the sky. Tap for moonrise/moonset, percent illuminated, days to the next phase, and continuously updated RA/Dec, Az/Alt, and compass direction — so you know where and when to aim for imaging or visual observation.
— The Sun: Sunrise/sunset, RA/Dec, Az/Alt, compass direction, current Julian date, and both GMST and LMST — practical for session planning.
— Planets & Messier objects: Positions, rise/set where applicable, RA/Dec, Az/Alt, and compass direction. Naked-eye filtering can hide Uranus and Neptune when you want only naked-eye planets.
— Comets: Real-time positions and magnitude estimates from orbital elements, including currently visible and newly reported objects.
— Transient events (upgrade): Aurora possibility alerts from current and predicted Kp; meteor shower alerts around peak dates (default five-day lead, configurable 1–30); and the next solar or lunar eclipse visible from your site, with magnitude and 1st–4th contact timings on the Details screen. Alerts appear on the watchface and in-app (meteors along the planisphere’s top edge; auroras below the planisphere, with an in-map aurora image when forecast).
— Optional Tile: Add StarHalo™ 2 to your Wear tile carousel for one-tap access without leaving your preferred watchface.
Why astronomers choose StarHalo™ 2
PRECISION: Positions are computed from established astrometric sources, including work associated with the U.S. Naval Observatory, the Royal Observatory at Greenwich, JPL, the International Astronomical Union (IAU), and VSOP87 planetary theory from the Bureau des Longitudes (Paris), among others.
FIELD-READY CUSTOMIZATION: Show or hide Sun, Moon, planets, stars, constellation lines, comets, and Milky Way; choose dark sky or real-time day/twilight tinting; and set digital element colors — including a red night-vision mode that preserves dark adaptation.
COMPATIBILITY: Works with Wear OS smartwatches running Wear 5.0 and above (app + free WFF watchface front-end).
StarHalo™ 2 — a living sky on your wrist.
