Well, if it happens before 2020, it'll be in 2018. That's just how the orbits line up (the next window is late spring 2018, with summer 2020 being the window af

Well, if it happens before 2020, it'll be in 2018. That's just how the orbits line up (the next window is late spring 2018, with summer 2020 being the window after that).