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Orbital Period Calculator

Orbital Period Equation:

\[ T = 2 \pi \sqrt{\frac{a^3}{G M}} \]

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1. What is the Orbital Period Equation?

The orbital period equation calculates the time it takes for an object to complete one full orbit around a central body. It is derived from Kepler's third law of planetary motion and is fundamental in celestial mechanics and astrophysics.

2. How Does the Calculator Work?

The calculator uses the orbital period equation:

\[ T = 2 \pi \sqrt{\frac{a^3}{G M}} \]

Where:

Explanation: The equation shows that the orbital period squared is proportional to the semi-major axis cubed, as described by Kepler's third law.

3. Importance of Orbital Period Calculation

Details: Calculating orbital periods is essential for understanding celestial mechanics, planning space missions, satellite deployment, and studying planetary systems.

4. Using the Calculator

Tips: Enter semi-major axis in meters and central body mass in kilograms. All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the semi-major axis?
A: The semi-major axis is half the longest diameter of an elliptical orbit, representing the average distance between the orbiting body and the central body.

Q2: Can this equation be used for circular orbits?
A: Yes, for circular orbits, the semi-major axis is equal to the radius of the orbit.

Q3: What units should be used for accurate results?
A: For the equation to work correctly, use meters for distance, kilograms for mass, and the result will be in seconds.

Q4: Does this equation work for all orbital systems?
A: This equation applies to two-body systems where one body is significantly more massive than the other, which is typical for planetary systems.

Q5: How accurate is this calculation?
A: The calculation is mathematically exact for ideal two-body systems, but real-world factors like other gravitational influences may cause slight variations.

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