The maximum distance from the earth to the sun (at aphelion) is 1.521 1011 m, and the distance of closest approach (at perihelion) is 1.471 1011 m. the earth's orbital speed at perihelion is 3.027 104 m/s. ignore the effect of the moon and other planets. (a) determine the earth's orbital speed at aphelion. m/s (b) determine the kinetic and potential energies of the earth–sun system at perihelion. kp = j up = j (c) determine the kinetic and potential energies at aphelion. ka = j ua = j (d)is the total energy constant