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Is tonight worth the drive, and if it is, what should you point at? Noctography answers both, for anywhere in the world. And now it will show you the shot itself: the real sky over the real ground of a spot you have never stood on.
Add it to your home screen and it behaves like an app.
A handful of tools that talk to each other. Everything is worked out on your own device from public forecast, orbital and elevation data: there is no server deciding things for you, and nothing to sign up to.
A straight answer first, then the best window of the night and the tiles that explain why: cloud through the dark hours, air and wind, sunset and moonrise, the darkness window, real-world Bortle, meteors, aurora, airglow, the Milky Way core, bright ISS and Starlink passes, and a comet when there is one genuinely worth a camera. Looking ahead shows the next fortnight night by night, or as a month of moons.
Hold the phone up and the sky is drawn over the camera, so you can scout a spot in daylight. Or switch to Scout and the camera is replaced by the actual landscape around your pin, built from elevation data with satellite imagery laid over it, lit by whatever moon is up. Aim with a finger, scroll the time from one night into the next, and plan a shot at a place you have never been. Stars, constellations, coloured trails and your lens, all in the right place.
Open the whole horizon from the zenith to well below your feet, laid flat the way a stitch prints. Draw the box, or let it fit the Milky Way arch for you, and it counts the frames for your lens and overlap, row by row. Turn the frames off and what is left is roughly the picture you would come home with.
Tonight’s best subjects, each shown as a small picture of the actual view at its best moment from where you are standing, through your lens. Tap one and you are there.
Press the shutter in Sky AR, in the field or from your sofa, and the frame is kept with its aim, lens and moment. Every composition tells you the next nights the sky returns to it, and they all sit on a map, so the good ones do not get forgotten. Alongside it, a simple log of the nights you went out and what you shot.
Solar wind measured at L1 and refreshed every minute, the measured geomagnetic index, where the arc would stand from your spot and how high, your own skyline in the poleward direction, and separate thresholds for the camera and the eye. Plus live reports from other people, which are worth more than any of it.
Shower activity against moon, cloud and sky darkness, with an hour-by-hour chart of the night. The headline figure is what you can realistically expect to see, not the theoretical rate on the poster.
Pin your spot to the metre on satellite imagery. See the sky brightness around you, or tonight’s real-world Bortle with the moon and haze counted in. And your own skyline, in colour, with the light pollution washed in behind it by direction.
Sensor, lens and aperture, saved to your device. It gives you your field of view and how long you can hold the shutter before the stars trail, and every other screen reads it. Star trail planning and the panorama calculator live here too.
Six colour schemes, and night vision throughout. Obsidian and gold leaf by default, with five alternatives a tap away. One more tap turns the whole app red on black so it does not wreck your dark adaptation, canvas and charts included. It remembers both between visits.
I am Paul Haworth, a landscape astrophotographer and filmmaker based in the Cambridgeshire Fens, in the east of England. I spend a lot of nights standing in fields waiting for the sky to do something worth photographing.
The problem was never a shortage of information. It was that the information lived in six different places: one site for cloud, another for the moon, a light pollution map, a meteor calendar, a satellite tracker, and none of them answered the only question that matters at five o'clock on a Tuesday afternoon: is tonight worth it?
So I built the thing I wanted. It pulls the forecast, works out the astronomy on your phone, and gives you a straight answer. Then, if you are going out, it tells you when the sky will be darkest, what is worth pointing at, whether it will fit your lens, whether to pack dew straps, and whether the mist is going to ruin it anyway.
It works anywhere. Give it a location and it reads the light pollution atlas, the forecast and the sky for that spot, in either hemisphere: the only thing that is particularly British about it is me.
It is free because it was always for me and my friends first. If it saves you a cold hour working something out on the back of your hand, you can buy me a coffee.
Nothing here is guesswork dressed up as data. Sun, moon, star and meteor radiant positions are computed in your browser. Cloud, humidity, temperature, dew point, wind and visibility come from Open-Meteo. Sky darkness comes from David Lorenz's 2025 light pollution atlas, baked into the app. Aurora comes from the NOAA Space Weather Prediction Center: the planetary K index, the OVATION model, and real-time solar wind measured at the L1 point. Shower parameters are hand-encoded from the International Meteor Organization working list. Satellite passes are propagated with SGP4 against CelesTrak orbital elements, on your device. The ground in Scout and your skyline come from AWS Terrain Tiles with Esri World Imagery over the top, and comets from the observers of COBS.
Every source is listed and credited inside the app, under More, Credits and privacy. If I have got something wrong, and I am sure I have somewhere, do tell me.
You need three things at once: full astronomical darkness, no moon, and the galactic core above the horizon. When that happens depends on where you are: north of the equator the core season runs roughly February to October and the core stays fairly low in the south; from the southern hemisphere it climbs far higher, and the season shifts. Noctography works all three out for your own location and shows where they overlap.
The published Bortle class for a site describes a perfect, moonless night, which is rarely the night you are standing in. Real-world Bortle starts from the atlas value for your location, then adds moonlight, haze from humidity, and town glow scattered back down by thin cloud, and converts the result back to a Bortle class. A Bortle 3 site under a gibbous moon genuinely performs like a Bortle 5 one.
It depends on your pixel pitch as much as your focal length, which is why the old 500 rule is generous on a dense sensor. Noctography uses the NPF rule and gives you two readings: pin-sharp, meaning no trailing at all, and relaxed, meaning trailing you will not notice in normal viewing and printing. In the framing view it goes further and corrects for the fastest star actually in your frame, which near the pole is worth a stop or more for nothing.
Often only photograph it. A dark-adapted eye runs on rod vision, which is colour-blind and roughly five to ten times less sensitive than a camera sensor, so your camera will frequently detect an aurora before you do, and sometimes it never gets bright enough to see by eye. Noctography draws the camera threshold and the eye threshold separately, and moves both with the moonlight, cloud and haze on the night.
Far fewer than the quoted ZHR, which assumes a perfect observer under a perfect sky with the radiant overhead. The real number falls with radiant height, moonlight, light pollution and cloud. A shower quoted at 100 an hour might realistically be 25 from a rural site at mid latitudes, and less again where the radiant never climbs high. Noctography will tell you which you are getting.
Yes, and you do not even need to be there. Hold your phone up and Sky AR draws the sky over the camera, so you can scout in daylight. Or use Scout, which draws the real landscape of any location from elevation data and satellite imagery, and scroll the clock to the night you want. The core, the arch, the moon and your lens all sit where they will actually be.
It depends on focal length, sensor, orientation and overlap. Thirty percent overlap is the minimum for reliable stitching; forty to fifty is safer for night skies, where there is little detail for the stitcher to grip. A 24mm lens on full frame, portrait, at forty percent overlap needs about 44 degrees between frames.
Radiation fog forms on exactly the nights that look most promising: a clear sky lets the ground radiate its heat away, the air cools to its dew point, and with no wind to mix it, mist forms at ground level. Noctography warns when those three line up.
Yes, and there is no account. It runs in your browser and keeps your location on your own device.
It takes about five seconds to tell you whether to bother.
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