  The terrestrial planets formed by accretion of asteroid-like objects within
the inner solar system's protoplanetary disk. Previous works have found that
forming a small-mass Mars requires the disk to contain little mass beyond ~1.5
au (i.e., the disk mass was concentrated within this boundary). The asteroid
belt also holds crucial information about the origin of such a narrow disk.
Several scenarios may produce a narrow disk. However, simultaneously
replicating the four terrestrial planets and the inner solar system properties
remains elusive. Here, we found that chaotic excitation of disk objects
generated by a near-resonant configuration of Jupiter-Saturn can create a
narrow disk, allowing the formation of the terrestrial planets and the asteroid
belt. Our simulations showed that this mechanism could typically deplete a
massive disk beyond ~1.5 au on a 5-10 Myr timescale. The resulting terrestrial
systems reproduced the current orbits and masses of Venus, Earth and Mars.
Adding an inner region disk component within ~0.8-0.9 au allowed several
terrestrial systems to simultaneously form analogues of the four terrestrial
planets. Our terrestrial systems also frequently satisfied additional
constraints: Moon-forming giant impacts occurring after a median ~30-55 Myr,
late impactors represented by disk objects formed within 2 au, and effective
water delivery during the first 10-20 Myr of Earth's formation. Finally, our
model asteroid belt explained the asteroid belt's orbital structure, small mass
and taxonomy (S-, C- and D/P-types).
