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How to Calculate Satellite Period

What is Satellite Period?

Satellite orbital period (Kepler third law) depends on orbital radius and central body mass: T² ∝ a³.

Formula

Apply T = 2π√(a³/GM)
T
2π√(a³/GM) — 2π√(a³/GM)
GM
GM value — Variable used in the calculation

Step-by-Step Guide

  1. 1Input orbital radius or planet name with altitude
  2. 2Apply T = 2π√(a³/GM)
  3. 3Results show period in hours/days

Worked Examples

Input
ISS at 400 km altitude around Earth
Result
T ≈ 90 minutes
16 orbits per day

Common Mistakes to Avoid

  • Confusing orbital radius with altitude
  • Forgetting Earth radius in altitude conversion

Frequently Asked Questions

Does satellite speed change with altitude?

Yes, inverse √r relationship; lower orbits faster.

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