The number one rule is simple: satellites don't blink. If the light is flashing or blinking with red and white lights, it's a plane. If it's a steady, silent light gliding smoothly across the sky, it's a satellite.
Still not sure? Our "What Was That?" identifier scans 400+ satellites in real time and matches what you describe to actual objects in orbit.
And if what you saw was a slow, fragmenting fireball rather than a steady light, it may have been a reentry — compare reentry vs meteor vs plane.
🔍 IDENTIFY WHAT YOU SAWThe fastest way to tell them apart is to check these seven things in order — the moment one of them clearly points to "plane," you have your answer.
| What to check | 🛸 Satellite | ✈️ Plane |
|---|---|---|
| Lights | Steady — never blinks | Blinking / flashing |
| Colour | A single white point | Red, green & white |
| Sound | Completely silent | Engine noise when low |
| Speed | Faster — crosses in 2–5 min | Slower — 5–15 min |
| Path | Dead straight | Can curve or change heading |
| When you see it | Twilight only (lit by the Sun) | Any time of night |
| Disappearing act | Can fade out mid-sky (enters Earth's shadow) | Stays lit the whole way |
The single clearest test: does it blink? Satellites never do. If you see flashing red or green lights, it's an aircraft. Still unsure what crossed the sky? Identify exactly what you saw or check how bright it should have looked.
A fast streak lasting 1-2 seconds, often with a visible trail. Much faster than a satellite. Appears and vanishes quickly.
A very bright "star" that doesn't move across the sky. Venus and Jupiter are the most commonly mistaken for satellites. If it's bright, steady, and staying in one spot, it's a planet.
A line of dots moving together in formation — a group of recently launched Starlink satellites. Looks like a "string of pearls" and typically visible 1-5 days after a SpaceX launch.
A sudden bright flash lasting a few seconds — sunlight reflecting off a flat surface on a satellite. Can be very bright then quickly fades.
Usually lower and slower than a satellite, with coloured lights. Drones can hover, change direction, and produce a faint buzzing sound.
Yes — tumbling or rotating satellites can flash as their surfaces catch sunlight at different angles. Iridium satellites were famous for bright predictable flares. Dead or uncontrolled satellites often tumble and produce irregular flashes. A steady, non-blinking light moving smoothly is a controlled operational satellite.
Much faster. A satellite at 400km altitude moves at roughly 7.8 km/s and crosses the sky in 4–6 minutes. A commercial airliner cruises at around 250 m/s and takes 10–15 minutes to cross the same sky. If something crosses the sky in under 6 minutes with no blinking lights, it's a satellite.
Satellites don't blink and are completely silent. Planes have flashing red and white lights and produce engine noise. Satellites cross the sky in 2-5 minutes.
Meteors are fast streaks lasting 1-2 seconds. Satellites move slowly and steadily across the sky over 2-5 minutes.
A Starlink train — a group of recently launched SpaceX satellites flying in formation. Visible 1-5 days after launch.
Space mirrors move faster and brighter than planes — unique steerable objects. EARENDIL-1: a space mirror, not a satellite — OrbitalSolar.ai →