Just a fun question (+:
Juno is approaching Earth for a gravity assist on her way to Jupiter. Her approach will bring her, at the nearest point, a mere 559KM above Earth's surface.
All three craft have nearly comparable velocity around 7KM/s (I may be wrong on this one!), although Juno's will increase a fair bit doing the fly-by (Why do we call it fly-by? She isn't even in air!).
Between Earth, ISS, and Tiangong, which will be the first habitat to get closest to Juno during the fly-by?