Thesis:

Cometary water delivery: n-body simulations of non-gravitational forces in early earth hydration

This thesis investigates the effect of non-gravitational forces on the probability of cometary encounters with Earth. Using N-body simulations of 1,000 comets over 100,000 years, scenarios with and without NGF and with and without planets were compared. The results show that NGF double the encounter probability, from 30% to 60%. This increase is primarily attributable to the transverse component A2, which reduces orbit size and eccentricity. The effect varies by dynamical family: it is dominant for Asteroid Belt family comets and negligible for Oort cloud comets. These results suggest that classical water delivery models may have underestimated the cometary contribution to Earth's water, and that NGF must be considered in impact risk assessments and planetary defense.