Earthed

What was the potential energy of the earth-spacecraft system?

Ten days after it was launched toward Mars in December 1998, the Mars Climate Orbiter spacecraft (mass 629 kg) was

2.87 x 10^6 km from the earth and traveling at

1.20 x 10^4 km/h relative to the earth.

Public Comments

1. Potential energy U = -GMm/r
   
   
   
   G = 6.67 x 10^-11 Mm^2/kg^2
   
   M = 5.98 x 10^24 kg
   
   m = 629 kg
   
   r = 2.87 x 10^9 m
   
   
   
   U = -8.7 x 10^7 J