  Embryos of the Moon and the Earth may have formed as a result of contraction
of a common parental rarefied condensation. The required angular momentum of
this condensation could largely be acquired in a collision of two rarefied
condensations producing the parental condensation. With the subsequent growth
of embryos of the Moon and the Earth taken into account, the total mass of
as-formed embryos needed to reach the current angular momentum of the
Earth-Moon system could be below 0.01 of the Earth mass. For the low lunar iron
abundance to be reproduced with the growth of originally iron-depleted embryos
of the Moon and the Earth just by the accretion of planetesimals, the mass of
the lunar embryo should have increased by a factor of 1.3 at the most. The
maximum increase in the mass of the Earth embryo due to the accumulation of
planetesimals in a gas-free medium is then threefold, and the current
terrestrial iron abundance is not attained. If the embryos are assumed to have
grown just by accumulating solid planetesimals (without the ejection of matter
from the embryos), it is hard to reproduce the current lunar and terrestrial
iron abundances at any initial abundance in the embryos. For the current lunar
iron abundance to be reproduced, the amount of matter ejected from the Earth
embryo and infalling onto the Moon embryo should have been an order of
magnitude larger than the sum of the overall mass of planetesimals infalling
directly on the Moon embryo and the initial mass of the Moon embryo, which had
formed from the parental condensation, if the original embryo had the same iron
abundance as the planetesimals. The greater part of matter incorporated into
the Moon embryo could be ejected from the Earth in its multiple collisions with
planetesimals (and smaller bodies).
