NRT-EWR generally flies pretty far south of Alaska to take advantage of the jet stream. You would need a flight that: (a) flies farther north; and (b) flies at night. Flights from EWR to Asia meet the first criterion, but most of the trip is in daylight. EWR to India could be a better bet. But you also need to sit on the north side of the plane, and the northern lights have to active on the day you fly. After multiple trips, I have yet to have seen them from a plane.