title: A 100,000-year periodicity in the accretion rate of interplanetary dust
abstract: Numerical modeling of the orbital evolution of interplanetary dust particles revealed that, over the past 1.2 million years, the rate of accretion of dust by Earth has varied by a factor of 2 to 3. These variations display a 100,000-year periodicity and are anticorrelated with Earth's changing orbital eccentricity. Extraterrestrial helium-3 concentrations in a deep-sea sediment core display a similar periodicity but are 50,000 years out of phase with the predicted variations. Also, because collisions between large bodies in the asteroid belt are inevitable, it is expected that large-amplitude stochastic variations on 10(7)- to 10(8)-year time scales would be superimposed on the 10(5)-year periodic variations.
authors.affiliation: S. J. Kortenkamp, Department of Terrestrial Magnetism, Carnegie Institution of Washington, 5241 Broad Branch Road NW, Washington, DC 20015, USA. E-mail: kortenka@dtm.ciw.edu S. F. Dermott, Department of Astronomy, University of Florida, 211 Space.
authors.initials: SJ
authors.lastname: Kortenkamp
authors.initials: SF
authors.lastname: Dermott