What was that in the sky?
A moving light. A string of lights in a perfect line. A slow, silent streak. Tell azmth roughly when and where you saw it, and it will check every low-orbit satellite against your sky at that exact moment and tell you what it was. Then you can watch the replay.
When did you see it?
Where were you?
Which way were you looking? (optional)
What did it look like? (optional)
Location is needed to reconstruct your sky.
Common sightings
I saw a line of bright lights moving across the sky. What was it?
Almost certainly a Starlink train: a batch of newly launched Starlink satellites still flying close together, which looks like a string of pearls crossing the sky. They are most visible in the first days after a launch, shortly after sunset or before sunrise. Use the tool above to confirm which launch it was.
I saw a single bright light moving steadily, with no blinking. What was it?
A steady, non-blinking light that crosses the sky in a few minutes is typically a satellite reflecting sunlight, and the brightest one by far is the International Space Station. Blinking lights are aircraft. The tool above checks which satellites were over you at that moment.
Why did nothing match my sighting?
The catalog covers active satellites and tracked objects in low orbit. If nothing matches well, you probably saw an aircraft, a meteor, a rocket launch or re-entry, or a bright planet. An honest "no match" beats a wrong answer.
How far back can it identify a sighting?
About a week. Satellite orbits are predicted from regularly refreshed orbital elements, and accuracy degrades as you go further from the present. Within a day or two of the sighting, matches are very reliable.
Does it work anywhere in the world?
Yes. Pick any location (or use your own), any time in the last week, and azmth reconstructs the sky above that point, checking more than 15,000 satellites computed in your browser.