When does the ISS pass over tonight?
When does the ISS pass over tonight?
The International Space Station orbits Earth every 90 minutes, and when a pass lines up with twilight at your location, it's often the brightest object in the sky — a steady white light crossing from horizon to horizon in about five minutes. No telescope needed.
This tool computes tonight's visible passes for your city from current orbital data: what time to step outside, which direction to face, and how high and bright the pass will be.
Passes are only visible when the station is sunlit while your sky is dark — typically within a couple of hours after sunset or before sunrise — which is why some weeks have passes every night and others have none.
Check a major city
How it works
The ISS is visible when two conditions align: it's overhead during your nighttime, and it's still lit by the sun (not yet in Earth's shadow). That's usually a 30–90 minute window after sunset or before sunrise. We compute tonight's passes using the latest orbital data from CelesTrak and score whether conditions — altitude, brightness, duration, and cloud cover — add up to a worthwhile view.