### Abstract

A systematic study of the motion backward and forward in time from a uniform distribution of bodies entering a planet's Hill sphere yields a mapping of the contribution to the planet's rotation from planetesimals as a function of their source in heliocentric orbital element space. The mapping allows determination of the contribution to rotation from any assumed distribution of heliocentric planetesimal orbits. For example, it can systematically reproduce earlier results from Monte-Carlo studies of contributions to rotational angular momentum. With our method of calculation, contributions to planetary rotation can be interpreted in terms of the arrival geometries at the planet's Hill sphere and the subsequent two-body motion inside the Hill sphere leading to impact. Prograde rotation is strongly favored if a planet grows in a relatively quiescent population of planetesimals with accretion nibbling at the edges of its feeding zone. However, if the impacting population were dominated by large bodies with high relative velocity, the direction and magnitude of rotation would be random.

Original language | English (US) |
---|---|

Pages (from-to) | 384-400 |

Number of pages | 17 |

Journal | Icarus |

Volume | 129 |

Issue number | 2 |

DOIs | |

State | Published - Oct 1997 |

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### ASJC Scopus subject areas

- Space and Planetary Science
- Astronomy and Astrophysics

### Cite this

*Icarus*,

*129*(2), 384-400. https://doi.org/10.1006/icar.1997.5777

**Sources of planetary rotation : Mapping planetesimals' contributions to angular momentum.** / Greenberg, Richard J.; Fischer, Mark; Valsecchi, G. B.; Carusi, A.

Research output: Contribution to journal › Article

*Icarus*, vol. 129, no. 2, pp. 384-400. https://doi.org/10.1006/icar.1997.5777

}

TY - JOUR

T1 - Sources of planetary rotation

T2 - Mapping planetesimals' contributions to angular momentum

AU - Greenberg, Richard J.

AU - Fischer, Mark

AU - Valsecchi, G. B.

AU - Carusi, A.

PY - 1997/10

Y1 - 1997/10

N2 - A systematic study of the motion backward and forward in time from a uniform distribution of bodies entering a planet's Hill sphere yields a mapping of the contribution to the planet's rotation from planetesimals as a function of their source in heliocentric orbital element space. The mapping allows determination of the contribution to rotation from any assumed distribution of heliocentric planetesimal orbits. For example, it can systematically reproduce earlier results from Monte-Carlo studies of contributions to rotational angular momentum. With our method of calculation, contributions to planetary rotation can be interpreted in terms of the arrival geometries at the planet's Hill sphere and the subsequent two-body motion inside the Hill sphere leading to impact. Prograde rotation is strongly favored if a planet grows in a relatively quiescent population of planetesimals with accretion nibbling at the edges of its feeding zone. However, if the impacting population were dominated by large bodies with high relative velocity, the direction and magnitude of rotation would be random.

AB - A systematic study of the motion backward and forward in time from a uniform distribution of bodies entering a planet's Hill sphere yields a mapping of the contribution to the planet's rotation from planetesimals as a function of their source in heliocentric orbital element space. The mapping allows determination of the contribution to rotation from any assumed distribution of heliocentric planetesimal orbits. For example, it can systematically reproduce earlier results from Monte-Carlo studies of contributions to rotational angular momentum. With our method of calculation, contributions to planetary rotation can be interpreted in terms of the arrival geometries at the planet's Hill sphere and the subsequent two-body motion inside the Hill sphere leading to impact. Prograde rotation is strongly favored if a planet grows in a relatively quiescent population of planetesimals with accretion nibbling at the edges of its feeding zone. However, if the impacting population were dominated by large bodies with high relative velocity, the direction and magnitude of rotation would be random.

UR - http://www.scopus.com/inward/record.url?scp=0031256339&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0031256339&partnerID=8YFLogxK

U2 - 10.1006/icar.1997.5777

DO - 10.1006/icar.1997.5777

M3 - Article

VL - 129

SP - 384

EP - 400

JO - Icarus

JF - Icarus

SN - 0019-1035

IS - 2

ER -