Moon phase calendar for your city: every night's phase, illumination, moonrise and moonset, distance and size, and how big it is on your lens.
Milky Way nights calendar
Which nights of the next year the Milky Way core is visible from your location: dark sky, no Moon, core high enough, grouped into runs. Free.
Name the place you will be standing and the tool returns the nights over the next twelve months when the galactic core is actually shootable from there — grouped into runs, each with the hours the core is up and how high it climbs. Give it the dates of a trip and it judges those nights one by one instead. Free, no account, nothing stored.
What it does, and why it is here
Photographing the Milky Way core needs three conditions at once, and any one of them alone is a wasted drive.
The core has to be above the horizon, which happens only in the Milky Way season and only for part of the night. The sky has to be astronomically dark, which is later than sunset and much later in summer at high latitude. And the Moon has to be out of the way — a gibbous moon washes the core out completely, whatever the forecast says.
Each of those is a calculation, and they only matter where they overlap. That overlap is what this page computes: not a season, not a moon phase, but the actual list of nights, with the hours.
The other thing it does is tell you honestly when the answer is never. Latitude decides almost everything, because the core sits at about 29 degrees south: from far enough north it barely clears the horizon, or does not clear it at all. A tool that returned an empty table there would look broken; this one says so, and says why.
What you fill in
- City — where you will be standing, not where you live. Latitude does most of the work here: the core never climbs higher than 90° minus your distance from 29° south, which is the single number that decides whether this is worth planning at all.
- Your stay, optional — a first and a last night within the twelve months ahead. Give them and the answer keeps those nights only, each with its own verdict. This is the trip-planning mode: you already know the dates, and you want to know which nights of the week away are the ones to set an alarm for.
- Fridays and Saturdays only — the filter for anyone whose astrophotography has to fit around a working week.
What you get back
- When to go — the nights grouped into runs rather than listed one by one. Good nights arrive in clusters around each new moon, so a run is the actual unit of a plan: “the week of the 12th”, not “the 12th, the 13th, the 14th”.
- Every night kept — the full list underneath, each with the night’s date, the hour the core comes up, how long it stays usable, how high it gets, and the Moon that night.
- Core height and season — the two figures that say whether a night is a photograph or a technicality. A core at 12° is behind every tree on the horizon; at 40° it stands clear.
- Night by night during the stay, when you gave dates — each night of the trip with its verdict, including the bad ones and the reason.
- A card to share for a run, when you want to send someone the plan.
- Or “not from here” — a straight answer when the latitude does not allow it, rather than an empty table.
What it does not do
No weather, and that is the condition that actually decides most nights. The tool gives you the nights that are astronomically possible; a forecast tells you which of them will be clear, and that is a separate check made two days out, not a year ahead.
It does not know your light pollution either. A perfect astronomical night from a city centre still shows nothing: the core needs a genuinely dark site, and the drive to one is yours to plan.
And it plans the core — the bright bulge in Sagittarius that people mean by “the Milky Way”. The band itself arcs across the sky all year; it is the core that has a season.
The three conditions, and what each one costs
| Condition | What it means | What fails it |
|---|---|---|
| Core above the horizon | Season and hour, decided by your latitude | Winter; or being too far north for it at all |
| Astronomical darkness | Sun more than 18° below the horizon | Summer nights at high latitude, which never get there |
| Moon out of the way | Set, or thin enough not to wash the sky | Anything past a fat crescent |
The second row is the cruel one for northern Europe: the core season peaks in summer, and summer is exactly when the sky at those latitudes never goes fully dark. That is why the good runs cluster at the ends of the season rather than in the middle of it.
Questions
Is it free? Do I need an account?
Free, no account, no limit.
Why is there only one field?
Because a place is enough. Everything else — season, darkness, moon, hours — follows from the latitude, the longitude and the date. The other fields exist only to narrow the answer to a trip or to weekends.
It says no nights at all. Is it broken?
Probably not. From far enough north the core never rises high enough to be worth photographing, and the tool says so rather than listing nights that would disappoint you. Try a location further south.
Does it account for light pollution?
No. It answers the astronomy; the darkness of your particular site is something to check on a light-pollution map.
What about the rest of the Milky Way?
The band is visible all year. The season and the hours here are for the core, which is the bright part everyone is actually after.
Are the times local?
Yes, in the time zone of the place you named, daylight saving included.
How far ahead does it look?
Twelve months, which covers a whole season and the start of the next.
When is the Milky Way season?
Roughly spring to early autumn in the northern hemisphere, and it shifts with latitude — earlier and longer the further south you go. The answer gives yours rather than a generic range.
Sources and further reading
- Galactic centre — the core, and why it sits at 29° south.
- Astronomical twilight — the 18° that defines a dark sky.
- Bortle scale — how dark a site actually is.
Explore
More tools like this one
Picked from the catalog by what this page is about — the closest ones first. Each tag opens its whole family.
When the Sun or Moon lines up with a street, a bridge or a ridge from where you stand: give a bearing or a landmark, get twelve months of dates.
What colour the clear sky is over any city, right now or at a chosen moment: the gradient, hex codes and CSS, the light of the hour and when it changes.