That line of lights in the sky is a Starlink satellite train
If you just watched a straight line of evenly spaced lights drift silently across the sky, you saw a batch of SpaceX Starlink satellites — not aircraft, not a meteor, and not a UFO.
How to know in ten seconds
Starlink satellites move in a single straight line, all at the same speed and brightness, with no flashing lights and no sound. Aircraft always blink red and green. Meteors last a second or two. A Starlink train takes several minutes to cross the sky, and often the lights vanish one by one partway across.
Is a Starlink train passing over you tonight?
This checks the live orbital data for satellite batches that are still flying low enough to be bright, then works out when they next cross your sky. Your location is used in your browser only — it is never sent to us.
How to be sure it was Starlink
- Several lights in a straight line, evenly spaced like beads on a string
- All the same brightness, all moving at the same speed, holding formation
- Completely silent — no engine noise at any point
- Takes 4–6 minutes to cross from one horizon to the other
- Lights often fade out one after another in mid-sky, as they enter Earth's shadow
- Seen in the hour or two after sunset, or before sunrise
- If the lights blink or flash red/green, it is an aircraft
- If it lasted only a second or two, it was a meteor
Why they fly in a line
A single Falcon 9 launch carries 20 to 30 Starlink satellites at once. They are released together at roughly 300 km — much lower than their final orbit — and separate very gently. For the first few days they stay bunched along the same orbital path, which is what produces the famous chain of lights.
After that, each satellite raises itself toward its operating altitude near 550 km using its own ion thruster, and they gradually spread out around the orbit. Within a few weeks the train has dissolved into individual satellites that look like ordinary moving stars. This is why a tight train is only visible for a short window after each launch — and why the sky check above will often tell you the current batches have already spread out.
Why the lights suddenly disappear
Satellites make no light of their own; they only reflect sunlight. When you see them, the sun has already set for you on the ground but is still shining on them high above. The moment they cross into Earth's shadow they wink out — often one after another, in the same order they were travelling. That vanishing act is the single clearest sign you were watching satellites.
Common questions
Is it a UFO?
No. Starlink launches have been the single most common cause of UFO reports since 2019. The giveaway is the regularity: perfectly even spacing and identical speed are what a man-made deployment looks like, and exactly what unexplained phenomena do not.
How often can I see a Starlink train?
A tightly bunched train is only visible for a few days after a launch, and only during the dark window after sunset or before sunrise when the satellites are still catching sunlight. Individual Starlink satellites pass overhead most clear nights, but they look like single moving stars rather than a chain.
How many Starlink satellites are up there?
More than 10,000 are currently tracked in orbit — by far the largest satellite constellation ever built. Most sit at about 550 km. TrackSat follows all of them live, along with roughly 5,000 other active satellites.
Why does the train look tighter in some videos than what I saw?
Almost every viral Starlink video was filmed within a day or two of a launch, when the satellites are still packed closely together. If you watched a batch that launched a few weeks ago, you would have seen the same satellites strung much further apart — a slow procession of separate dots rather than a chain.
Can I predict when the next one passes over me?
Yes. Pass times are fully predictable from the satellites' orbital data. The sky check above does this for the current low-flying batches, and the TrackSat app does it continuously for your location, including alerts before a pass begins.