Escape Speed on Mars

The escape speed of each planet can be determined from the strength of the planet's gravity.

The escape speeds of planets will be proportional to the square root of the ratio of the mass of the planet divided by the radius of the planet (see page 210 of textbook, 5th edition)


Now we can apply this to Mars. It has a mass that is 0.11 times the Earth's and a radius that is 0.53 times the Earth's

so the escape speed will be the square root of 0.11/0.53 times the Earth's escape speed of 11.2 km/sec

escape speed of Mars = sqrt(0.11/0.53) x 11.2 km/sec
................................................ = sqrt(.21) x 11.2 km/sec
................................................ = 0.45 x 11.2 km/sec
................................................ = 5.0 km/sec