The orbital period — the time to complete one loop — determines how far Earth rotates between each pass. That rotation shift is the engine behind all ground track patterns.
The orbital period — the time to complete one loop — determines how far Earth rotates between each pass. That rotation shift is the engine behind all ground track patterns.
A satellite at 400 km altitude does ~15.5 orbits per day. At 600 km it's ~15 orbits. At 800 km, ~14.5. Each orbit adds roughly the same westward shift.
Some missions are specifically designed so the track repeats after a precise number of orbits — making revisit geometry completely predictable.
The simple picture assumes a perfectly stable orbit. In reality, several effects slowly change the period and therefore the track.
Understanding period and Earth rotation is the key to predicting where a satellite will appear — and why map predictions drift when TLEs age.