The Kepler's 3rd Law calculator computes the orbital period (T), mass of the system (M), and the distance separating the objects (R). It also provides the Universal Gravity Constant(G). Click on any of the buttons (RIGHT) to see a calculator with Kepler's 3rd law solved for that chosen parameter.
Kepler's 3rd Law of planetary motion states that the orbital period (T), mass of the system (M), the distance separating the objects (R), and the Universal Gravity Constant (G) are related in the following formula:
where:
Distance Units: The calculator has length unit with defaults of au (astronomical units) which is the mean distance from the Sun to the Earth. However, users can automatically change the distance units on both the inputs to the calculator and the solved answers via the pull-down menu. The distance units are automatically handled and range from extremely small (nano-meters) to truly astronomical including au, light seconds, light minutes, light years, parsecs, kilo-light years and mega-parses.
Mass Units: The calculator has mass units that default to multiples of the mass of the sun (solar_mass). However, users can automatically change the mass units on both the inputs to the calculator and the solved answers via the pull-down menu. The mass units are automatically handled and range from extremely small (grains) to truly astronomical including Earth masses, Jupiter masses and Solar masses.
Time Units: The calculator has time duration units that default to days. However, users can automatically change the time units on both the inputs to the calculator and the solved answers via the pull-down menu. The time units are automatically handled and range from extremely small (nanoseconds) to large including weeks, months, years, decades and centuries. They also include sidereal day and sidereal years.
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