Planet Hop


Below is a chart which lists the gravitational pull (relative to Earth's) of each planet in our solar system. Also included in the chart is the number of Earth years it takes for that planet to make a complete revolution around the Sun. Your mission is to calculate your weight and age on each planet as you jump from one planet to the next.

Example: If the planet has a gravitational pull 2.5 times greater than that of Earth, then a 220 pound earthling would weigh 550 pounds on that planet. (2.5 x 220 = 550)

Example: It only takes the Earth 365.24 days to revolve once around the Sun. Due to their great distance from the Sun, some planets may take hundreds of Earth years to complete the same journey. If you take your age and divide it by the length of time it takes a particular planet to complete a revolution around the Sun, you can determine what your age would be in terms of that planet's year. For instance, if you are 10 years old on Earth and it takes Planet "Z" 20 years to complete a revolution, then you would only be .5 Planet "Z" years old (10 / 20 = .5). Keep in mind that the average lifespan of an earthling is 75 years. Once you have done the calculations using your actual age, do the activity using the age of 75 to see what your lifespan would be on each planet.


Now compute your age (in planet years) and weight on each planet. Type your answers into the boxes below, then press the "Check Me" button at the bottom of the page.

Planet Gravitational pull Revolutional period Your weight (pounds) Your age (years)
0.38 87.9 days Earth (1/4 of a year)
0.91 224.7 Earth days (2/3 of a year)
0.38 686.9 Earth days
2.54 11.86 Earth years
0.93 29.46 Earth years
0.8 84.01 Earth years
1.2 164.79 Earth years


The gravitational pull of the Sun is 28 times greater than that of Earth. If you could stand on the Sun, how much would you weigh?



The StarChild site is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA/ GSFC.

StarChild Authors: The StarChild Team
StarChild Graphics & Music: Acknowledgments
StarChild Project Leader: Dr. Laura A. Whitlock
Curator: J.D. Myers
Responsible NASA Official: Phil Newman