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Title: Chaotic Zones around Rotating Small Bodies

Abstract

Small bodies of the solar system, like asteroids, trans-Neptunian objects, cometary nuclei, and planetary satellites, with diameters smaller than 1000 km usually have irregular shapes, often resembling dumb-bells or contact binaries. The spinning of such a gravitating dumb-bell creates around it a zone of chaotic orbits. We determine its extent analytically and numerically. We find that the chaotic zone swells significantly if the rotation rate is decreased; in particular, the zone swells more than twice if the rotation rate is decreased 10 times with respect to the “centrifugal breakup” threshold. We illustrate the properties of the chaotic orbital zones in examples of the global orbital dynamics about asteroid 243 Ida (which has a moon, Dactyl, orbiting near the edge of the chaotic zone) and asteroid 25143 Itokawa.

Authors:
;  [1];  [2]
  1. Institut UTINAM, Observatoire des Sciences de l’Univers THETA, CNRS, Université de Franche-Comté, Besançon F-25030 (France)
  2. Laboratoire de Physique Théorique du CNRS, IRSAMC, Université de Toulouse, UPS, Toulouse F-31062 (France)
Publication Date:
OSTI Identifier:
22663549
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astronomical Journal (Online); Journal Volume: 153; Journal Issue: 6; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ASTEROIDS; CHAOS THEORY; COMETS; MOON; ORBITS; PLANETS; ROTATION; SHAPE; SOLAR SYSTEM; STABILITY; ZONES

Citation Formats

Lages, José, Shevchenko, Ivan I., and Shepelyansky, Dima L., E-mail: jose.lages@utinam.cnrs.fr. Chaotic Zones around Rotating Small Bodies. United States: N. p., 2017. Web. doi:10.3847/1538-3881/AA7203.
Lages, José, Shevchenko, Ivan I., & Shepelyansky, Dima L., E-mail: jose.lages@utinam.cnrs.fr. Chaotic Zones around Rotating Small Bodies. United States. doi:10.3847/1538-3881/AA7203.
Lages, José, Shevchenko, Ivan I., and Shepelyansky, Dima L., E-mail: jose.lages@utinam.cnrs.fr. Thu . "Chaotic Zones around Rotating Small Bodies". United States. doi:10.3847/1538-3881/AA7203.
@article{osti_22663549,
title = {Chaotic Zones around Rotating Small Bodies},
author = {Lages, José and Shevchenko, Ivan I. and Shepelyansky, Dima L., E-mail: jose.lages@utinam.cnrs.fr},
abstractNote = {Small bodies of the solar system, like asteroids, trans-Neptunian objects, cometary nuclei, and planetary satellites, with diameters smaller than 1000 km usually have irregular shapes, often resembling dumb-bells or contact binaries. The spinning of such a gravitating dumb-bell creates around it a zone of chaotic orbits. We determine its extent analytically and numerically. We find that the chaotic zone swells significantly if the rotation rate is decreased; in particular, the zone swells more than twice if the rotation rate is decreased 10 times with respect to the “centrifugal breakup” threshold. We illustrate the properties of the chaotic orbital zones in examples of the global orbital dynamics about asteroid 243 Ida (which has a moon, Dactyl, orbiting near the edge of the chaotic zone) and asteroid 25143 Itokawa.},
doi = {10.3847/1538-3881/AA7203},
journal = {Astronomical Journal (Online)},
number = 6,
volume = 153,
place = {United States},
year = {Thu Jun 01 00:00:00 EDT 2017},
month = {Thu Jun 01 00:00:00 EDT 2017}
}
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