Because of the timing of the pulses scientists have already determined that the two stars orbit each other once every 12 days.
(the timing of the pulses scientists; have determined; that the two stars orbit each other once every 12 days; T:already) Context(the timing of the pulses scientists have determined,List([11, 70))):(the two stars; orbit; each other; T:once every 12 days)
the timing of the pulses scientists have determined,List([11, 70))
the timing of the pulses scientists the two stars
have determined orbit
that the two stars orbit each other once every 12 days T:already
each other T:once every 12 days