Modeling of a Giant Exoring System Around the Substellar Companion J1407b

We model the complex light curve of 1SWASP J140747.93-394542.6, a ~16 Myr old star in the Sco-Cen OB association, with a giant ring system that fills a significant fraction of the Hill sphere of an unseen secondary companion, J1407b. The best ring model has 37 rings and extends out to a radius of 0.6 AU (90 million km), and the rings have an estimated total mass on the order of 1 M _⊕. The ring system has one clearly defined gap at 0.4 AU (61 million km), which we hypothesize is being cleared out by a < 0.8 M _⊕ exosatellite orbiting around the secondary companion.