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Orbital Period Calculator

Orbital Period Equation:

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

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m³/kg s²

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1. What is the Orbital Period Equation?

The orbital period equation, derived from Kepler's third law of planetary motion, calculates the time it takes for an object to complete one full orbit around a central body. It's 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 square of the orbital period is proportional to the cube of the semi-major axis of its orbit.

3. Importance of Orbital Period Calculation

Details: Calculating orbital periods is essential for satellite deployment, space mission planning, astronomical research, and understanding celestial mechanics.

4. Using the Calculator

Tips: Enter the semi-major axis in meters, central body mass in kilograms, and gravitational constant. 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: Why is the gravitational constant important?
A: The gravitational constant (G) is a fundamental physical constant that determines the strength of the gravitational force between objects.

Q3: Does this equation work for circular orbits?
A: Yes, for circular orbits, the semi-major axis is simply the radius of the circle.

Q4: Can I use this for planets orbiting the sun?
A: Absolutely. This equation works for any two bodies where one is much more massive than the other, such as planets orbiting stars.

Q5: What units should I use?
A: For accurate results, use meters for distance, kilograms for mass, and the standard value for G (6.67430 × 10⁻¹¹ m³/kg s²).

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