What is a satellite constellation?
A satellite constellation is a fleet of satellites working together as a single system. GPS needs 24+ satellites so that four are always above your horizon; Starlink operates over 10,000 to blanket the planet in broadband. Constellations — not single satellites — are why the number of objects in orbit has tripled since 2019.
Navigation constellations
GPS (USA, 31 active), Galileo (Europe, ~30), GLONASS (Russia, ~24) and BeiDou (China, ~45) all work the same way: each satellite broadcasts an ultra-precise timestamp, and your phone computes its position from the tiny delays between four or more signals. The atomic clocks aboard are accurate to nanoseconds — and even need Einstein's relativity corrections to work.
Internet mega-constellations
Starlink flies at ~550 km so signals take ~25 ms instead of the ~600 ms of traditional GEO satellite internet. Each Falcon 9 adds 20–60 satellites, which briefly form the famous 'Starlink train' — a line of lights crossing the night sky in the days after each launch.
See every constellation live, colour-coded, on Cosmik's satellite map — filter Starlink, GPS, OneWeb and more with one tap.
Frequently asked questions
What is a satellite constellation?
A coordinated fleet of satellites working as one system — like Starlink's thousands of broadband satellites or GPS's 31 navigation satellites. One satellite covers a spot; a constellation covers the planet.
How many Starlink satellites are there?
Thousands — the largest constellation ever flown, and growing with nearly every Falcon 9 launch. Track the live count and every orbital plane on Cosmik's 3D map.
Why do I see a line of lights in the sky?
That's a freshly launched Starlink 'train' — 20-60 satellites still bunched together in the days after deployment, catching sunlight in a row. They spread out within weeks. Cosmik shows when the next train passes over you.
Keep exploring
See it yourself tonight
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