Predicted positions of {beta}Pictoris b and c

Both planets' masses are within ~1{sigma} of the predictions of hot-start evolutionary models and exclude cold starts. We validate our approach on N-body synthetic data integrated using REBOUND. We show that orvara can account for three-body effects in the {beta}Pic system down to a level ~5 times smaller than the GRAVITY uncertainties.

Systematics in the masses and orbital parameters from orvara's approximate treatment of multiplanet orbits are a factor of ~5 smaller than the uncertainties we derive here. Future GRAVITY observations will improve the constraints on {beta}Picc's mass and (especially) eccentricity, but improved constraints on the mass of {beta}Picb will likely require years of additional radial velocity monitoring and improved precision from future Gaia data releases.