From a high cliff, Papillon observes a cove where he realizes the waves are powerful enough to carry a man out to sea and to the nearby mainland.
That's from the Wikipedia article for Papillon, a 1973 film based on a true story. Papillon is French for butterfly and it's the nickname of the main character who has a large butterfly tattoo.
He's a safe cracker wrongfully convicted of murder and sentenced to life imprisonment in a harsh prison system in French Guiana. At some point, he's transferred to a facility on an island.
Others have built rafts to try to escape and have all been washed back to the base of the cliffs by strong waves, breaking up their rafts and probably killing them. Papillon spends substantial time observing the waves and concludes there's a pattern.
My recollection is he says there is a pattern of seven waves which repeats.
He believes if he leaves at the right time, he can get out. He does successfully escape.
A reasonable use of astrology is trying to find a way to thread the needle for difficult situations. Some of them may end up looking a bit like Papillon's escape from the island where you somehow need to go "north" in the face of all forces seeming to push you "south."
This may be especially pertinent if you wish to use astrology to develop gravity maps for space travel. My understanding is that it is possible to sail against the wind if you know what you are doing with a sailboat.