The identical twins Speedo and Goslo join a migration from the Earth to Planet X, 17.5 ly away in a reference frame in which both planets are at rest. The twins, of the same age, depart at the same moment on different spacecraft. Speedo's spacecraft travels steadily at 0.965c and Goslo's at 0.670c. (a) Calculate the age difference between the twins after Goslo's spacecraft lands on Planet X. yr (b) Which twin is older