Recall that a PHO is defined as an object withH622 and a
MOID < 0.05 AU with respect to the Earth’s orbit. We investigated
the evolution of the MOID for our impactor population as a function of time before impact as shown inFig. 2. All the impactors’s
osculating orbits were integrated using the JPL’s N-body integrator
incorporating the effects of the Sun, eight planets, and dwarf planets Pluto and Ceres and minor planets Vesta and Pallas. MOIDs
were then calculated at different times before impact using the
synthetic objects’s integrated osculating orbits at the time of interest, not the orbit derived from synthetic observations of the object.
We see that as the time of impact approaches the MOID decreases