The International Space Station is the easiest spaceship you will ever see. It's the size of a football field, orbits 400 kilometers up, and reflects enough sunlight to outshine every star in the sky. When it passes over your town at the right time, it's genuinely hard to miss — if you know when to look.
What you'll see
A brilliant, steady, white-gold point of light that rises from one horizon and glides to the other in two to six minutes. No blinking, no sound. At its best the ISS reaches magnitude −4 — brighter than Venus. People regularly mistake it for a plane with landing lights until they notice it never gets closer, never blinks, and crosses the entire sky.
Why it isn't visible every night
Three things have to line up:
- The orbit has to pass near you. The ISS circles Earth every ~92 minutes on a path tilted 51.6° to the equator, and the Earth rotates underneath it. Some days its track crosses your sky; some days it doesn't.
- The timing has to be right. You need the station in sunlight while your ground is dark — the couple of hours after sunset and before sunrise.
- The pass has to be high enough. A pass that only skims 10° above the horizon is easy to lose behind trees and haze. The good ones climb 40° or higher; the great ones go nearly overhead.
The result: from any given backyard, good evening ISS passes come in clusters — a stretch of several nights with visible passes, then a gap of days or weeks. That's why a prediction beats checking the sky at random, every time.
How to watch one, step by step
- Get the exact time and direction. ISS passes are predictable to the second. You want three numbers: when it rises, which compass direction it appears from, and how high it will climb.
- Head out a few minutes early. Find open sky in the rise direction — most passes in the northern hemisphere start somewhere in the west.
- Watch the horizon region, then be patient. The station starts faint and low, then brightens fast as it climbs.
- Follow it across. A high pass takes about five minutes horizon to horizon. If it suddenly fades and vanishes mid-sky, you just watched it fly into Earth's shadow — orbital sunset in real time.
Making it effortless
Everything above is what Flyby automates. It computes every visible ISS pass for your exact location, scores whether it's actually worth going outside for (brightness, elevation, your local light pollution — here's how satellite visibility works), and sends a notification that tells you when to step out and which way to face — down to the second. During the pass, Live Activities put the countdown and direction arc on your Lock Screen, and the AR view points your phone straight at the station. There are usually 3 to 6 people living up there; Flyby will show you who's aboard as it crosses.