  Fractions of asteroidal particles, particles originating beyond Jupiter's
orbit (including trans-Neptunian particles), and cometary particles originating
inside Jupiter's orbit among zodiacal dust are estimated to be about 1/3 each,
with a possible deviation from 1/3 up to 0.1-0.2. These estimates were based on
the comparison of our models of the zodiacal cloud that use results of
numerical integration of the orbital evolution of dust particles produced by
asteroids, comets, and trans-Neptunian objects with different observations
(e.g., WHAM [Wisconsin H-Alpha Mapper spectrometer] observations of spectra of
zodiacal light, the number density at different distances from the Sun). The
fraction of particles produced by Encke-type comets (with e~0.8-0.9) does not
exceed 0.15 of the overall population. The estimated fraction of particles
produced by long-period and Halley-type comets among zodiacal dust also does
not exceed 0.1-0.15. Though trans-Neptunian particles fit different
observations of dust inside Jupiter's orbit, they cannot be dominant in the
zodiacal cloud because studies of the distribution of number density with a
distance from the Sun shows that trans-Neptunian particles cannot be dominant
between orbits of Jupiter and Saturn. Mean eccentricities of zodiacal particles
that better fit the WHAM observations were about 0.2-0.5, with a more probable
value of about 0.3.
