Boeing 787 draws an airplane over the United States

Recently, pilots of a Boeing 787 testing a new set of Rolls Royce engines, fulfilled their FAA required long-distance endurance requirement in an unusual way. The Boeing pilots decided to have a little fun and fly a flight path that traced a giant 787 Dreamliner airplane in the sky. The strange route showed up on flight tracking sites like Flight Aware. How far do you think the plane traveled?  How long was it in the air?  What would you need to do, create or think about to figure this out?