Live Sky Map: Tonight's Sky Over You
The map above is a full-screen planetarium that draws the sky for your exact spot on Earth, right now or at any moment between the years 1700 and 2200. Drag to look around, pinch or scroll to zoom, and tap anything, a star, a planet, the Moon, to learn what it is, when it rises and sets, and whether your own sky is dark enough to show it. The sky you can actually see tonight, explained.
What the map shows
The dome renders about 9,000 real stars, every star brighter than magnitude 6.5, the classic naked-eye limit under a dark sky, drawn from the European Space Agency's Hipparcos catalog with each star's true color. Zoom in and an optional binocular-depth layer adds about 32,500 fainter stars, to about magnitude 8, from the XHIP compilation, fading with your Bortle sky the same way the naked-eye stars do. On top of that it computes live positions for the Sun, the Moon and all the planets (plus Pluto), draws the 88 constellation figures with their names, shades the sky through every stage of twilight, and shows the Milky Way as a labeled schematic band. The Moon shows its real phase, with the crescent's horns pointing the correct way for your view, at its average angular size by default.
By default, below the horizon line the map draws ground, not stars, so what you see matches what your real horizon hides. When you want to know where something is while it is down, the layers panel offers an optional Look through the Earth chart view: turn it on and the ground becomes see-through while the stars, planets and figures below the horizon are drawn faded, in their true computed positions, with the horizon line kept so you always know where the real edge of your sky is. It is a diagram of position, not a view of the sky: a body below your horizon is hidden by the whole bulk of the Earth, and the map never pretends otherwise. Everything is computed in your browser by the open-source Astronomy Engine; after loading, the page talks to no third-party service except the optional place lookup (finding or naming a city), and turning on the pointing mode loads one small declination file from this site.
How to read the sky
Direction: the letters around the horizon are compass points; N is due north. Whatever the map shows above the S marker is what you see when you face south. Height: astronomers measure height in degrees of altitude, from 0 at the horizon to 90 straight overhead; your fist at arm's length spans about 10 degrees, so an object at 30 degrees altitude is three fists up. Brightness: star brightness is measured in magnitudes, and the scale runs backward: magnitude 0 is brilliant, magnitude 6 is the naked-eye limit under a dark sky.
To match the map to your real sky, open the layers panel and set your Bortle class, the standard 1 to 9 rating of light pollution. The map then fades exactly the stars your sky hides: a Bortle 8 city sky keeps only a few hundred stars, which is honest, not broken. The same fade runs through twilight, so stars appear in the evening in the true order of brightness, Sirius and the planets first.
What is up tonight?
The strip along the bottom of the map ranks tonight's best objects for your location: the Moon, the visible planets, and more than two dozen famous deep-sky showpieces, each with the time it climbs highest and a dot showing whether it is within reach of your sky and equipment. Tap a chip and the camera flies there. For the full ranked table with rise and set times, see Today in the Sky.
Everything the map can do
- Tap to identify: every star, planet and constellation gets a plain-language card: what it is, how high it sits right now, when it rises, peaks and sets tonight, and whether your eyes, binoculars or a telescope will show it.
- Search with no server to break: type any star, planet, constellation, meteor shower, or Messier or Caldwell name (typos are fine) and the camera flies to it. The search index ships with the page: it needs no server.
- Time travel: scrub minutes or centuries, jump to sunset, the middle of the night, or sunrise (computed for the map's location), or play time at up to a day per second and watch the sky wheel.
- Honest realism: the Bortle setting and twilight fade show the sky you will actually see, never a fantasy deep field. The "perfect dark sky" view is labeled as exactly that.
- Red night mode: one tap turns the whole page deep red to protect your dark adaptation at the eyepiece, with a screen dimmer on top.
- Find the planets instantly: colored rings mark every planet that is up, edge arrows point toward the ones outside your view so you can pan straight to them, and opening search with an empty box lists the whole solar system with live positions and rise times.
- Meteor shower radiants: when a shower is active and your sky is dark, the map marks its radiant and shades the 30 to 45 degree band where trails are longest. Search or tap the shower to see its peak night, the moonlight to expect, and your personal best viewing window, with the honest reminder that meteors can appear anywhere overhead.
- Moon meets planet: when the Moon closes in on a bright planet or a star it can hide, a dashed line marks the pair with the gap labeled, and a nightly check finds the closest approach for your exact spot. If the Moon covers a planet, its dot slips behind the disk and the map says so. One tap adds the pairing to your calendar.
- Messier and Caldwell markers: once your sky is dark, the map draws the classic chart symbols for the 110 Messier and 109 Caldwell deep-sky objects, galaxies, star clusters and nebulae (a few Messier curiosities, like the M40 double star and the M73 asterism, are labeled rather than drawn as symbols). Tap any one for what it is and an honest estimate of whether your binoculars or telescope can reach it under your sky. The chart itself stays symbols and words; tap a marker and its card adds a real reference photo, clearly labeled, next to what your own eyes will show.
- Star-hop from a bright star: open any deep-sky object, faint star, or Uranus or Neptune and the map plots a route from a bright, easy-to-find anchor star to it, one finder field at a time, through waypoints unmistakable enough to recognize. It draws Telrad, finder and eyepiece circles at true sky scale, and walks you through the hops one step at a time. If you observe through a star diagonal or a Newtonian, flip the whole map to a mirror image or upside down so it matches exactly what you see in the eyepiece.
- Point at the sky (beta, on phones): tap the point-at-the-sky button and the map turns as you move your phone, using the motion and compass sensors. Compasses are only good to about 10 degrees, so if the map sits a little off, tap the object you are really aiming at and press Align (or drag sideways); the correction is remembered on your device, and magnetic declination is corrected automatically.
- Shareable views: the link in your address bar always encodes the exact view: place, time, direction, zoom and selection. Copy it and anyone opens the same sky.
- Fast and lightweight: the viewer is about 300 KB compressed to start, and the binocular-depth star layer loads only if you zoom in, so it opens in seconds even on a phone.
Keyboard shortcuts
Arrow keys look around; + and - zoom; , and . step time by ten minutes; / opens search; t opens the time controls; l opens layers; Escape closes any panel. Every control is reachable by Tab, and selections are announced to screen readers.
Accuracy, honestly stated
Sun, Moon and planet positions come from the MIT-licensed Astronomy Engine, accurate to well under a degree and reliable for roughly the years 1700 to 2200; the time scrubber is clamped to that range. Star positions are Hipparcos catalog values in the J2000 reference frame (the fainter binocular-depth stars come from the XHIP compilation, which is built on Hipparcos), carried through precession and nutation; annual aberration, up to about 20 arcseconds, is not modeled for stars, which is well over a hundred times below the whole-degree precision this map claims. Stellar proper motion is not applied either; the few fastest-moving bright stars drift by up to about half a degree at the far ends of that range. Atmospheric refraction is applied near the horizon using a standard-atmosphere model; real refraction at the horizon varies by several arcminutes with temperature and pressure. Altitudes and azimuths are shown to whole degrees and times to the minute: no decimal is displayed that the model cannot defend.
What this map deliberately does not do: it does not paint photographic deep-sky imagery onto the sky itself (the object card shows a labeled reference photo of what you tapped, but the dome stays a clean chart) or carry a billion-star catalog (the naked-eye sky ends near magnitude 6.5, and the optional binocular-depth layer stops at magnitude 8, this catalog's limit), it does not overlay the camera picture (the point-at-the-sky mode moves the map with your phone, but honestly, as a chart: phone compasses are typically within about 10 degrees, so a drag-to-align nudge is built in), it does not predict satellite passes, and it does not control telescopes. Tools that do those things well exist; this page would rather do the visible sky excellently.
Data sources
Stars: the ESA Hipparcos catalog (8,870 stars to magnitude 6.5, with B-V colors), plus an optional binocular-depth layer of about 32,500 more stars to magnitude 8 from the XHIP compilation (Anderson and Francis 2012) via d3-celestial. Star names: the IAU Catalog of Star Names. Deep-sky objects (the 110 Messier and 109 Caldwell markers), constellation figures and the schematic Milky Way outline: the d3-celestial project by Olaf Frohn (BSD-3-Clause), whose deep-sky positions trace to the Saguaro Astronomy Club database; the Caldwell numbers follow Patrick Moore's published list. Magnetic declination for the point-at-the-sky mode: the World Magnetic Model, on a coarse grid regenerated yearly. All positions computed in-browser by the Astronomy Engine (MIT). Full details on the methodology page.
Sky map questions, answered
What is that bright star I can see tonight?
It is often not a star at all. The brightest steady point in the evening or morning sky is usually Venus or Jupiter, and the brightest true star is Sirius. To find out exactly what you are seeing, set your location on the map above, point the view the same way, and tap the object: the map names it and tells you when it rises and sets.
Is this sky map free? Do I need an account or an app?
Yes, it is free, with no account and no app to install. The whole viewer downloads about 300 KB compressed to start and runs entirely in your browser, so it starts fast even on a slow connection; the optional binocular-depth star layer loads only when you zoom in.
How accurate is this sky map?
Sun, Moon and planet positions come from the open-source Astronomy Engine and are accurate to well under a degree, reliable for roughly the years 1700 to 2200. Stars come from the Hipparcos catalog, with the fainter binocular-depth layer from the XHIP compilation, all carried through precession and nutation. Altitudes and azimuths are shown to whole degrees and times to the minute, which is what the model honestly supports.
Why does the map show more stars than I can see?
By default the map draws the classic naked-eye sky: about 9,000 stars, down to magnitude 6.5. Zoom in and an optional binocular-depth layer adds about 32,500 fainter stars, to about magnitude 8, the brightest of what 50 mm binoculars can show. Most real skies are brighter than that: from a city you may see only a few hundred stars, and from a bright inner city just a few dozen. Open the layers panel and set your Bortle class, and the map fades out the stars your sky hides, the deep layer included. The map also fades stars through twilight, so at noon it honestly shows none.
Does the sky map track or store my location?
No. By default it only guesses a starting city from your device's time zone, entirely on your device. If you tap 'Use my location', your browser's coordinates are used locally to compute the sky, and they are sent once to a geocoding service only to look up your city's name for the label. Nothing is stored on any server and there is no account.
Can the sky map follow my phone as I point it at the sky?
On most phones, yes. Tap the point-at-the-sky button and the map turns as you move your phone, using the motion and compass sensors; iPhones ask for motion permission first. Phone compasses are only accurate to about 10 degrees, so if the map sits a little off, tap the object you are really aiming at (the Sun or Moon works well) and press Align; a gentle sideways drag also fine-tunes it, and magnetic declination for your location is corrected automatically. There is no camera overlay: the map stays a clean, readable star chart.
What time zone are the times on the sky map shown in?
Times follow your device's clock. If you point the map at a place whose local time is more than two hours from yours, a note appears saying how big the offset is, so a sunset listed at 3:40 am will not surprise you. Shared links can carry an explicit time zone, and the sunrise and sunset presets always use the sky location's real solar events.
Where should I look during a meteor shower?
Not at the radiant itself. A shower's meteors streak away from its radiant point, so trails look shortest right at the radiant and longer farther out. The practical sweet spot is the shaded band 30 to 45 degrees from the radiant, which this map draws for any shower that is active once your sky is dark. Search for the shower, or tap its card, to see the radiant marked on the dome along with its peak night, how much moonlight to expect, and your personal best viewing window. Published rates are ideal dark-sky ceilings, so real counts run lower, and shower meteors can appear anywhere overhead.
Can the map tell me when the Moon passes a planet?
Yes. When the Moon sits within a few degrees of a bright planet or a star it can hide, the map draws a dashed line between them with the separation labeled, and once a night it works out the closest approach for your exact location and offers a note like 'Tonight the Moon passes 0.8 degrees from Mars at 9:40 pm', with an add-to-calendar button. These times are topocentric, meaning they are computed for where you stand, so they can differ by up to a degree from the geocentric figures you see elsewhere, because the Moon is close enough that your spot on Earth changes its apparent position. If the Moon actually covers the planet, that is an occultation, and the exact timing depends on your location to within a few minutes.
What do the circle and square markers on the map mean?
They are the classic chart symbols for deep-sky objects, marking the 110 Messier and 109 Caldwell showpieces once your sky is dark, with the fainter ones filling in as you zoom in. A dotted circle is an open star cluster, a circle with a cross is a globular cluster, a square is a nebula or supernova remnant, a small circle with four ticks is a planetary nebula, and a flattened ellipse is a galaxy. Tap any marker to see what the object is and an honest estimate of whether your binoculars or telescope can reach it under your Bortle sky. The sky chart itself stays symbols and words, never a photograph painted on the dome; the card that opens when you tap a marker does add a real reference photo, clearly labeled as such, so you can compare what the object truly is with what your own sky will show. The galaxy ellipses on the chart are drawn without a tilt because we do not have their orientation angles and will not fake them.
How deep does the sky map go?
By default, to magnitude 6.5, the naked-eye limit. When you zoom in, an optional binocular-depth layer loads and adds about 32,500 fainter stars, down to about magnitude 8, the brightest of what 50 mm binoculars can show and this catalog's limit. That is not what binoculars actually reach: from a truly dark site 50 mm binoculars go fainter still. The layer fades with your Bortle setting and with twilight exactly like the naked-eye sky, so in a bright city or before the sky is fully dark it thins toward nothing, and a small badge tells you which.
Why can I only zoom in so far?
To keep it honest. The map limits how far you can zoom so it never shows a thin scatter of stars pretending to be a rich field. Once the binocular-depth layer has loaded there are real stars to fill a closer view, so the zoom limit doubles. If you turn that layer off, or twilight or your Bortle sky is too bright for it to show, the map eases back out to the naked-eye zoom limit, and the badge explains why.
How do I star-hop to something I cannot see?
Open the object on the map and press 'Star-hop from a bright star'. The map finds a chain of stars from a bright, easy-to-spot anchor star to your target, with every step no wider than your finder's field, and draws Telrad, finder and eyepiece circles at true sky scale so the hops match what you see through the glass. Press Next hop to walk the route one step at a time; each step tells you how far to move and in which drawn direction. If you observe through a star diagonal or a Newtonian, set 'Match what you see through' so the whole map mirrors or flips to match your view, and a badge reminds you that it is flipped. Star-hop opens once your target climbs above 10 degrees.
Can this map predict satellite passes?
No, and it does not pretend to. Predicting when the Space Station or a satellite will cross your sky needs live orbital data this page does not carry. Instead, get tonight's pass times from Heavens-Above or your favorite ISS app, open 'Plot a satellite pass' in the layers panel, and type in the start, highest and end points it lists (time, altitude, and compass direction). The map then draws the pass as an arc across your sky, with minute marks and a moving dot, so you know exactly where to look, and you can play it back before it happens. The arc is a smooth curve through your three points; a real pass bends a little near the horizon.
Does the sky map show real photos of these objects?
The chart itself does not: the dome stays clean symbols and words, so it only ever shows what you could line up against the real sky. But when you tap a planet or a deep-sky object, its card now includes a real reference photo from a telescope or passing spacecraft, clearly labeled as such and not your naked-eye view. It sits right next to the honest estimate of whether your eyes, binoculars or telescope can reach the object, so you can see what it truly is and what you will actually see through the glass. Ordinary stars stay as simple points, because even the largest telescopes cannot resolve most of them into a disk; only the planets and Pluto, the Sun and Moon, the Messier and Caldwell showpieces, and a few giant stars carry a photo.
Can the map show what is below the horizon?
Yes, as an optional chart view. By default the map draws ground below the horizon line, matching what your real horizon hides. Turn on 'Look through the Earth' in the layers panel and the ground becomes see-through: the stars, planets and constellation figures below the horizon are drawn faded, in their true computed positions, with the horizon line kept so you always know where the real edge of your sky is. It answers a question observers ask all the time, is the planet I want to watch up yet and which way is it, at a single glance. It is a diagram of position, not a real view, because you cannot actually see through the Earth, so nothing below the horizon is ever drawn as if your eye could reach it.
Keep exploring
Pair the map with Today in the Sky for tonight's full ranked list, the 88 Constellations catalog for every figure's story, the Telescope Calculator to know what your gear can reach, and the Moon Phase Calendar for the month ahead.
Want to leave the ground entirely? Voyage lets you fly the solar system from the outside, piloting a spacecraft to the planets at their real positions, weaving among Jupiter's moons and threading Saturn's rings. It is a planetarium show you can pilot, not a measurement, so this map stays the place for measured positions of the sky.