The implied multipole gravitational components could be added to the three body code to confirm this hypothesis. Furthermore, a much smaller amplitude modulation of the eccentricity, with the frequency of the apsidal motion, will likely remain. It would be interesting to compare this with the 32 year modulation observed in the timing of the primary eclipse. It also remains to study the possible dynamic origin of the perpendicular orbit. However, our Figures 5 and 6 show that for more than half of all relative inclinations, the observed triple systems would be unstable.
More work is needed to fully delimit the range.
There formation is interpreted in terms of multiple fragmentation of the original cloud with a distribution of initial angular momenta. Triple systems that form similarly might be expected to have initial relative inclinations that are random. This would place the majority of triples at unstable relative inclinations. Sufficiently extreme systems will experience collisions in the inner binary, leaving only the outer binary and a hole in the observed distribution of triple inclinations. Less extreme systems will escape collision, but will exhibit great variations in inner eccentricity and relative inclination over time.