The Nice Model and the LHB
- In Gomes et al.(2005) we saw that we can produce LHB by delaying the resonance crossing.
- Happens naturally if we use more reasonable initial conditions:
- Inner edge where particle dynamical lifetimes ~ nebula lifetimes.
- We performed several simulations and found crossing times near
700Myr for reasonable inner disk edges.
- We find that ~2x10-8 of the particles would hit the Moon.
- Given our disk of 35ME
~4x1021gm.
- 90% of material hits in first 30Myr.
- This destabilzes asteroid belt due to secular resonance sweeping.
- ~5 +/- 5 x 1021gm of asteroids hit Moon.
- This is consistent with observation of ~6x1021gm.
So, even through the outer solar system is the trigger for the LHB.
- Asteroids likely came in last and
- They may dominate the total mass.
- They undoubtedly dominated the basins because comets likely had a steep SFD.
- The Nice model predicts Trojans and the cold Kuiper belt are from the primordial disk.
- They have steep SFD (dn/dr~r-6.5!) while the asteroids do not.
Iap
Mars
