How many TJ of energy is necessary to get a 300 ton spacecraft from the surface of Venus to 1) orbit at 60520km and 2) to leave the planets gravitational field? 12104km Venus diameter 6052 is Venus radius therefore. 4,9 * 10ˇ24 kg Venus mass 60520km orbit radius T-1,9 earth days spaceship 300 000kg Given answers: 14,99 TJ; 15,78 TJ 3. The attempt at a solution 1)energy at orbit -1/2Gmm/R -1/2 *(6,67*10ˇ-11)*(4,9 * 10ˇ24)*300000/60520000 (dist to orbit)= -0,81TJ and then to get the work required i divide -0,81 TJ-(-16,2 TJ) = 15,39 TJ (the other one comes from below) 2) since binding energy=gravity ´-Gmm/R = -(6,67*10ˇ-11)*(4,9 * 10ˇ24)*300000/6052000(Venus radius) =-16,2TJ So what exactly am calculating here? No match with given answers?