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See the space station pass over

The International Space Station looks like a bright, steady star gliding across the sky in a few minutes. Here is when you can see it from your city, which way to look, and where it is right now.

City

Passes you can see

Getting the latest orbit data…

The orbit data is downloaded from CelesTrak, and the passes are worked out on your phone. Your city or location is never sent anywhere. The orbit data (public) is kept on this device for 6 hours so the page doesn't download it again.

Where is it now?

How to spot it

Why only at dawn and dusk

The station has no lights you can see from the ground: it shines because sunlight bounces off it. You see it when your sky is dark but the station, 400 km up, is still in sunlight. That happens for a while after sunset and before sunrise.

What it looks like

A bright white point that does not blink and moves steadily, faster than a plane. It can be brighter than any star. A pass lasts from 1 to 6 minutes. Sometimes it fades out in mid-sky as it enters the Earth's shadow.

Reading the times

"Appears" is when it rises 10° above the horizon (about one fist at arm's length), or comes out of shadow. "Max height" of 90° would be straight overhead: anything above 40° is a great pass. Be outside a few minutes early.

Why predictions change

The station slowly drops in the thin air at that height and is boosted up again now and then. Orbit data is updated several times a day, so check again on the day: times can move by a minute or more.

Sources: Orbit data (two-line element set for the ISS, catalogue number 25544) from CelesTrak (celestrak.org, Dr T. S. Kelso), which updates it several times a day; downloaded live in your browser. Orbit calculation: SGP4 via satellite.js (MIT licence), the standard model for these orbit data. Sun position: Astronomy Engine by Don Cross (MIT licence). A pass counts as visible when the station is at least 10° above the horizon, in sunlight (outside a cylindrical Earth shadow), and the Sun is at least 6° below your horizon; NASA's Spot the Station uses similar rules. Brightness is a rough guide from the distance to the station. Check: our positions match an independent SGP4 calculation (PyEphem) for the same orbit data to within 0.01°. Speed and height: NASA (about 28,000 km/h, about 400 km up, one orbit about every 90 minutes). Times are UAE time (UTC+4) and can shift by a minute or more as the orbit data is updated.