3ª Lei Kepler T
- Created by
- Renato Passos, Eng. de Software
- Reviewed by
- Renato Passos, Eng. de Software
Last updated: Apr 18, 2026
About this calculator
The Kepler Orbit Calculator - Period applies Kepler's third law to calculate the orbital period of a planet or celestial object. The formula T² = (4π²/GM)·a³ relates the orbital period (T) to the average distance of the object from the central body (a), where G is the gravitational constant and M is the mass of the central body. This helps to better understand the orbital dynamics of celestial bodies.
Kepler's third law is fundamental to astronomy, as it relates the physical characteristics of a planetary system. It works based on the idea that the gravitational force acting on a planet is proportional to the mass of the central body and inversely proportional to the square of the distance between them. With this law, it is possible to predict the orbital period of planets and other celestial objects.
The Kepler Orbit Calculator - Period is useful in various situations, such as the study of planetary systems, the analysis of exoplanets, and the understanding of astronomical phenomena. However, it is essential to be careful with the units used and ensure that the input values are accurate, as small errors can lead to significant discrepancies in the results.
It is important to note that Kepler's third law assumes a circular orbit and neglects the influence of other celestial bodies. Therefore, the results obtained should be interpreted with caution, considering the limitations and assumptions of the law.
Frequently asked questions
What is Kepler's third law?
Kepler's third law relates the orbital period of a planet to its average distance from the Sun, stating that the square of the period is proportional to the cube of the distance.
What units are used in the calculator?
The units used are: seconds for the orbital period (T), cubic meters per kilogram per second squared (m³/kg/s²) for the gravitational constant (G), kilograms (kg) for the mass of the central body (M), and meters (m) for the average distance (a).
Can I use the calculator for other celestial bodies?
Yes, the calculator can be used for other celestial bodies, such as moons, asteroids, and comets, as long as you know the mass of the central body and the average distance of the object from the central body.
Does the calculator assume circular orbits?
Yes, the calculator assumes circular orbits. For elliptical orbits, other formulas and considerations are necessary.
How can I minimize errors in the results?
To minimize errors, ensure that you use consistent units and accurate values for the mass of the central body and the average distance of the object.