Dynamical Constraints on Nontransiting Planets Orbiting TRAPPIST-1
Daniel Jontof-Hutter et al 2018 AJ 155 239
The observed configuration of the TRAPPIST-1 system is unlikely if a Jovian-mass planet inclined by ≥3° to the transiting planet exists within 0.53 AU, constraining a putative planet beyond the transiting seven planets.