> It was you who assumed initially that the 80 years was "ship time". Diane merely said she saw on TLC that a journey to Alpha Centauri at .1c would take a round trip of 80 years.

Actually, I saw that nuclear engines could propel a space vessel at 0.1c. The 80 years I based on Alpha Centauri being 4ly from Earth (hence, 4*0.1 = 40, doubled for round trip... I didn't include sticking around to explore time, because I didn't feel it relevent to the equation... after all, they're not going to be traveling at 0.1c to explore this area in detail, right?)

In any event, the 80 years is just based on an 8ly round trip at 0.1c.

Di "I should shut up now" ane