Theian Orbital Evolution Amidst the Planetary Leftovers

The formation of the Earth's Moon commonly involves a theory where Theia, a Mars-sized object [1,2], encounters the proto-Earth via a Giant Impact. Updated measurements based on lunar samples indicate an age of the Moon to be roughly 70-110 Myr [3,4] younger than the Calcium Aluminum Inclusions in the chondritic meteorites. This implies that Theia likely existed for 20-80 Myr as one of five surviving terrestrial embryos [5] embedded in a planetesimal disk leftover from the late stage of planetary accretion [6,7]. Simulations of a Moon-forming giant impact using smooth particle hydrodynamics have been successful in providing insight into what initial conditions are required with respect to the collision parameters and compositions [8]. But the mass of the impactor is largely unconstrained and can vary depending on the chosen model [9,10]. Using a dynamical 5 terrestrial planet model we present our current work to understand how the penultimate orbit of Theia influences the early bombardment history of the terrestrial planets.