GUIDES / BASICS
How often does the ISS pass over my city?
By Jeroen Wouda · 2 November 2026 · Basics
The honest answer has two halves. The station passes over your latitude many times every day. It is visible from your city in a way worth going outside for in bursts, a few weeks at a time, separated by gaps of a similar length.
Both halves are true at once, and the gap between them is the thing most people find surprising.
Fifteen orbits a day, most of them useless
The station completes an orbit roughly every 92 minutes, which works out at a little over 15 orbits per day. Each orbit brings it over some part of the world, and each orbit crosses your latitude twice, once heading north and once heading south.
So why is tonight's sky empty? Because being overhead is only the first of three conditions, and it is the easiest one to meet.
The three conditions for a visible pass
A pass you can actually see needs all of the following.
- The station must be above your horizon. This happens several times a day, whether or not you notice.
- The station must be in sunlight. It is visible only by reflected sunlight. Once it enters the Earth's shadow it disappears, no matter how high it is.
- Your sky must be dark enough. If the sun is still up, or the sky is bright with twilight, a satellite at 400 kilometres has no chance against the background.
The middle condition is the one that does the work. The station is in sunlight for most of each orbit, but for part of it the Earth stands between the station and the sun, and during that stretch it is invisible from the ground below.
The overlap between "sunlit" and "your sky is dark" happens twice a day: shortly after sunset and shortly before sunrise. That is why almost every pass you will ever see falls in those windows. The full explanation is in why passes cluster at dusk and dawn, but the short version is that the station is high enough to still catch the sun while the ground beneath you has already turned away from it.
Why the passes come in seasons
Here is the part that catches people out. The evening window does not stay put. As the weeks pass, the station's orbital plane keeps its orientation in space while the Earth travels around the sun, so the moment when the station is both sunlit and over your horizon drifts earlier or later.
The result is a cycle. For a stretch of weeks the station appears in the evening sky, coming over during and after twilight several times a week. Then the geometry moves on, the evening passes become lower and fainter and eventually land after the station has entered shadow, and the evening show stops.
Some weeks later the morning passes begin. They behave the same way: several good passes a week, in the hour or two before sunrise, then a slow fade.
Between these two seasons there is a gap with no useful passes at all, usually of a few weeks. During that gap you can still find the station with a telescope or a good pair of binoculars in daylight if you know exactly where to point, but for the naked-eye observer it is simply gone.
So a reasonable expectation for a mid-latitude city is something like this: a few weeks of evening passes, a gap, a few weeks of morning passes, a longer gap, and then the evening season returns. The cycle repeats over months, not days. If you look up the station tonight and see nothing, that tells you almost nothing about tomorrow night.
What a good pass looks like
Within a season, not every pass is equal. Some are high and brilliant, crossing near the zenith in five or six minutes. Others graze the horizon at 12 degrees and are easy to miss behind a roof.
The difference is how close the orbital ground track runs to your city. The station's track shifts west with each orbit, so it sweeps a series of parallel lines across your region over successive passes. One of those lines will pass almost over you; the next will be a few hundred kilometres away, then further, and then the pattern comes back around.
Working it out for your own city
Three numbers are worth checking for each candidate pass.
Maximum elevation. Below 20 degrees you are fighting haze and rooftops. Above 40 degrees it is a good sight. Near 80 or 90 degrees it is spectacular and brief.
Direction of travel. From mid-northern latitudes the station usually rises in the west or south-west and sets in the east or north-east.
Time relative to twilight. The best passes sit in the hour or so after sunset or before sunrise, when the sky is dark enough to see the station but the station is still in sunlight. A pass listed for the middle of the night will usually be an invisible one, unless the station is high enough to stay lit, which for the ISS it is not for long.
Predictions also have a shelf life. The station's orbit is nudged by residual atmosphere and by reboost manoeuvres, and the error grows with the forecast horizon. A listing made for tonight is reliable. One made for three weeks ahead is an approximation, useful for planning a season rather than a minute.
Where to go next
- ISS passes has the current list for your city, refreshed from recent orbital data.
- The ISS orbit and the 51.6 degree inclination explains why the ground track behaves the way it does.
- Starlink or the space station? helps if the thing you spotted was bright but not quite right.
More guides
- Best time of year to watch the ISS — There is no single best month. The good weeks depend on the angle between the orbit and the Sun, and here is how that cycle works.
- How to photograph the ISS — A moving point of light, a dark sky and a camera, and what it takes to turn a pass into a photograph worth keeping.
- How to see the ISS tonight (without an app) — What to look for, when to look, and why an ordinary evening is often the wrong one — a plain guide to spotting the space station.