SKY · FIELD GUIDE
What Is the "Starlink Train" — and How to See It
A perfectly straight string of lights, evenly spaced, sliding silently across the sky like a procession. Not a plane, not a UFO — almost certainly a Starlink train. Here's the whole story.
If you've ever looked up and seen a tidy, evenly-spaced line of lights gliding silently across the sky — no flashing, no sound, just a procession of dots in single file — you saw a Starlink train. It's one of the most-reported "what was that?" sights of recent years, and the explanation is simpler (and less alien) than it looks.
What it is
SpaceX launches its Starlink internet satellites in big batches — often dozens at a time on a single rocket. When the rocket releases them, they all start out in nearly the same low orbit, packed close together. Seen from the ground in the days right after launch, that cluster reads as a straight line of evenly-spaced lights — the "string of pearls."
Each dot is one satellite, catching sunlight the same way the Space Station does. There's no engine glow and no sound; they're hundreds of kilometres up, moving in formation.
Why they line up — and why it doesn't last
The line is a temporary phase. After deployment, each satellite fires its own small thrusters to raise its orbit toward its final operating altitude. They climb at slightly different rates and slowly drift apart, so over the following days and weeks the tight train stretches, gaps open up, and eventually the satellites are spread evenly around the planet — invisible to the casual eye.
That's why the dramatic train is a short-lived window:
- First few days after a launch — tightest, brightest, most train-like.
- Up to a couple of weeks — still noticeable as a loose line.
- After that — dispersed and faint; you won't pick them out without trying.
Because new batches go up frequently, there's often a fresh train somewhere over the world on any given night — the challenge is just catching one from where you happen to be standing.
When and where to look
The same twilight rule that governs the Space Station applies here: you can only see a satellite when your sky is dark but the satellites high above are still in sunlight. That means:
- The hour or two after dusk, or
- The hour or two before dawn.
Starlink trains travel roughly west to east, like most low-orbit satellites. They're easy to recognise once you know the shape — a straight, silent, evenly-spaced line, quite unlike a single bright Space Station pass or a blinking aircraft.
How to catch the next one over you
Predicting a train is trickier than predicting the ISS, because there are many of them and the freshest batches change with each launch. The reliable approach is a location-aware pass finder: it pulls the latest published orbital data for recent Starlink batches and works out which one next crosses your sky during a dark window — then tells you when to look and which way. Step outside a couple of minutes early, face west, and watch for the line to rise and drift over.
A quick reassurance
Starlink trains are bright and strange-looking enough that they're a regular source of UFO reports — but they're entirely explainable, predictable, and (for fresh batches) genuinely lovely to watch. If the line you saw was straight, evenly spaced, silent, and moving steadily, you can be confident: it was a freshly-launched fleet of satellites, still flying in formation before going their separate ways.
Frequently asked questions
What is the Starlink train?
It's a batch of newly-launched Starlink satellites — dozens at a time — still bunched close together in a line before they spread out and climb to their working orbits. For a few weeks after each launch they're visible from the ground as a 'string of pearls': a row of evenly-spaced lights gliding silently across the sky.
Why are the satellites in a line?
A single rocket releases the whole batch into nearly the same low orbit at once, so they start out tightly clustered. Over the following days and weeks they use onboard thrusters to raise their orbits and drift apart, gradually losing the neat 'train' formation until they're spread evenly around the planet.
How long is a Starlink train visible?
The tight, dramatic train is best in the first few days after a launch and typically remains noticeable for a couple of weeks before the satellites disperse. Because new batches launch frequently, there's often a fresh train somewhere in the sky — the trick is being at the right place at the right time after dusk.
When and where should I look?
Like most satellites, a Starlink train is visible when your sky is dark but the satellites high above are still sunlit — the hour or two after dusk and before dawn. They travel roughly west-to-east. A location-aware pass finder will tell you when the next visible train crosses your exact sky.
Are they always visible to the naked eye?
Only fresh, low batches are reliably naked-eye. Once Starlink satellites reach their higher operational orbit and spread out they become much fainter and far harder to notice. So the 'train' you can actually see is almost always a recent launch.
SEE IT LIVE
Everything in this guide is on the live sky map.