  Our Solar system is almost entirely devoid of material interior to Mercury's
orbit, in sharp contrast to the multiple Earth masses of material commonly
residing within the analogous region of extrasolar planetary systems. Recent
work has suggested that Jupiter's orbital migration early in the Solar system's
history fragmented primordial planetary material within the inner Solar System.
However, the reason for the absence of subsequent planet formation within 0.4AU
remains unsolved. Here, we show that the up debris interior to Mercury's
current orbit is susceptible to outward migration driven by the early Solar
wind, enhanced by the Sun's primordial rapid rotation and strong magnetic
field. The ram pressure arising from azimuthal motion of the Solar wind plasma
transported ~100m-sized objects and smaller from 0.1AU out to the terrestrial
planet-forming zone within the suspected ~30-50,Myr timespan of the Earth's
formation. The mass of material within this size class typically exceeds
Mercury, and can rival that of Earth. Consequently, the present-day region of
terrestrial planets and the asteroid belt has been supplied by a large mass of
material from the innermost, hot Solar system, providing a potential
explanation for the evidence of high-temperature alteration within some
asteroids and the high iron content of Mercury.
