Sextant: Night Sky Objects

Hold your phone up to the sky and Sextant shows what's there: stars, planets, the Moon in its phase, the Milky Way, and the satellite crossing overhead right now.

Built for the moment you see something moving up there and want to know what it is. Every lit satellite gets a short fading trail, so the dot on your screen matches the one crossing the sky. Tap it: Sextant names it, tells you how bright it is and how far away, and counts down to when it fades into Earth's shadow or sets.

ALERTS
• Star a satellite and get a heads-up before each pass you can see (2 to 30 minutes ahead, your choice): when, where it crosses, how high, how bright
• Tonight's highlights: one line at sunset on the nights worth going out. Meteor shower peaks, the Moon beside a planet, planets at their closest, bright comets
• Worked out on your phone; nothing is sent anywhere

SATELLITES
• Thousands of satellites from CelesTrak's orbits, refreshed twice a day
• Motion trails and a pass track with minute-by-minute times
• "Overhead now": the bright satellites lit up right now, and which way they're heading
• The next day's visible passes for any satellite, a tap away from seeing it
• Works offline from the orbits it last downloaded

TONIGHT
• Visible tonight: the Moon, planets, bright satellites, constellations and deep-sky objects worth looking at between dusk and dawn
• An altitude chart for each over day, twilight and night, with rise, set and best time
• Satellite passes you can actually see: sunlit, against a dark sky

COMETS AND METEOR SHOWERS
• Comets from the Minor Planet Center's orbits, with tails pointing away from the Sun and a forecast of when each is brightest
• All 37 meteor showers on the IMO calendar: radiants on the sky while they're active, peak nights in Visible tonight with the Moon's interference
• For anything that isn't up tonight: the next night it is

THE SKY
• Point mode: aim your phone and the sky follows; pick anything and an arrow walks you to it
• Stars, planets, the Moon in its phase, and the Milky Way
• Constellation figures appear for the one you're looking at, or always, or never
• 21 famous clusters, nebulae and galaxies: the Pleiades, Andromeda, the Orion Nebula and more
• Time travel: drag the clock to see tonight at 3 a.m., or next week
• Night mode turns everything dim red to keep your eyes dark-adapted
• Search stars, planets, comets, meteor showers, constellations, deep-sky objects and satellites (by name or NORAD number); sort by brightness or height, filter to what's up now
• Favourites: star anything to keep it at the top of search
• Set your location by hand if you'd rather not share it

ACCURATE
Star and planet positions are tested against Stellarium to under half an arcminute; satellite positions and pass times against Skyfield to under a second; comet positions against Skyfield to under a tenth of an arcminute.

PRIVATE
No account, no ads, no tracking, no analytics. Your location is used on your phone to work out the sky and never leaves it. Alerts are scheduled on your phone too.