We report the discovery of two long-period giant planets from the Anglo-Australian Planet Search. HD 154857c is in a multiple-planet system, while HD 114613b appears to be solitary. HD 114613b has an orbital period P=10.5 years, and a minimum mass m sin i of 0.48 Jupiter masses; HD 154857c has P=9.5 years and m sin i=2.6 Jupiter masses. These new data confirm the planetary nature of the previously unconstrained long-period object in the HD 154857 system. We have performed detailed dynamical stability simulations which show that the HD 154857 two-planet system is stable on timescales of at least 100 million years. These results highlight the continued importance of legacy surveys with long observational baselines; these ongoing campaigns are critical for determining the population of Jupiter analogs, and hence of those planetary systems with architectures most like our own Solar system.
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