Enter the acceleration due to gravity (m/s^2) and the radius between the planet and object (m) into the Planet Mass Calculator. The calculator will evaluate and display the Planet Mass.

## Planet Mass Formula

The following formula is used to calculate the Planet Mass.

PM = a*r^2 / G
• Where PM is the Planet Mass (kg)
• a is the acceleration due to gravity (m/s^2)
• r is the radius between the planet and object (m)
• G is the gravitational constant (6.67408*10^-11)

To calculate the mass of a planet, multiply the acceleration due to gravity by the radius between the planet and object squared, then divide by the gravitational constant.

## How to Calculate Planet Mass?

The following example problems outline how to calculate Planet Mass.

Example Problem #1:

1. First, determine the acceleration due to gravity (m/s^2).
• The acceleration due to gravity (m/s^2) is given as: 9.81.
2. Next, determine the radius between the planet and object (m).
• The radius between the planet and object (m) is provided as: 500.
3. Finally, calculate the Planet Mass using the equation above:

PM = a*r^2 / G

The values given above are inserted into the equation below and the solution is calculated:

PM = 9.81*500^2 / 6.67408*10^-11 = 3.674e+16 (kg)

Example Problem #2:

For this problem, the variables needed are provided below:

acceleration due to gravity (m/s^2) = 9.81

radius between the planet and object (m) = 6000

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer.

PM = a*r^2 / G = ?