The dynamics of objects in the inner Edgeworth-Kuiper Bellt

JONES D., WILIAMS I.P., AND MELITA,M.D. THE DYNAMICS OF OBJECTS IN THE INNER EDGEWORTH-KUIPER BELLT.

EARTH, MOON, AND PLANETS

SPRINGER

Año: 2005 vol. 97 p. 435 - 458

0167-9295

Objects in 3:2 mean motion resonance with Neptune are protectedfrom close encounters with Neptune by the resonance. Bodies in orbits withsemi-major axis between 39.5 and about 42 AU are not protected by theresonance; indeed due to overlapping secular resonances, the eccentricities oforbits in this region are driven up so that a close encounter with Neptunebecomes inevitable. It is thus expected that such orbits are unstable. Thelist of known Trans-Neptunian objects shows a deficiency in the number ofobjects in this gap compared to the 43-50 AU region, but the gap is not empty.We numerically integrate models for the initial population in the gap, andalso all known objects over the age of the Solar System to determine whatfraction can survive. We find that this fraction is significantly less than theratio of the population in the gap to that in the main belt, suggesting thatsome mechanism must exist to introduce new members into the gap.By looking at the evolution of the test body orbits, we also determinethe manner in which they are lost. Though all have close encounters withNeptune, in most cases this does not lead to ejection from the Solar System,but rather to a reduced perihelion distance causing close encounters withsome or all of the other giant planets before being eventually lost from thesystem, with Saturn appearing to be the cause of the ejection of most of theobjects.