The origin of Pluto's peculiar orbit

Research output: Contribution to journalArticle

278 Citations (Scopus)

Abstract

THE origin of Pluto's unusual orbit - the most eccentric and inclined of all the planets - remains a mystery. The orbits of Pluto and Neptune overlap, but close approaches of these two planets are prevented by the existence of a resonance condition1: Pluto's orbital period is exactly 3/2 that of Neptune, which ensures that the conjunctions always occur near Pluto's aphelion. Long-term orbit integrations2-5 have uncovered other subtle resonances and near-resonances, and indicate that Pluto's orbit is chaotic yet remains macroscopically stable over billion-year timescales. A suggestion4 that the orbit may have evolved purely by chaotic dynamics appears unlikely in light of recent orbital stability studies6, unless one appeals to a well-timed collision to place Pluto in its stable orbit19. Here I show that Pluto could have acquired its current orbit during the late stages of planetary accretion, when the jovian planets underwent significant orbital migration as a result of encounters with residual planetesimals7. As Neptune moved outwards, a small body like Pluto in an initially circular orbit could have been captured into the 3:2 resonance, following which its orbital eccentricity would rise rapidly to its current Neptune-crossing value.

Original languageEnglish (US)
JournalNature
Volume365
Issue number6449
StatePublished - Oct 28 1993
Externally publishedYes

Fingerprint

Pluto (planet)
orbits
Neptune (planet)
planets
orbitals
conjunction
circular orbits
eccentrics
eccentricity
encounters
collisions

ASJC Scopus subject areas

  • General

Cite this

The origin of Pluto's peculiar orbit. / Malhotra, Renu.

In: Nature, Vol. 365, No. 6449, 28.10.1993.

Research output: Contribution to journalArticle

Malhotra, Renu. / The origin of Pluto's peculiar orbit. In: Nature. 1993 ; Vol. 365, No. 6449.
@article{cdfeb8d3a8654e24b6990baaecf72780,
title = "The origin of Pluto's peculiar orbit",
abstract = "THE origin of Pluto's unusual orbit - the most eccentric and inclined of all the planets - remains a mystery. The orbits of Pluto and Neptune overlap, but close approaches of these two planets are prevented by the existence of a resonance condition1: Pluto's orbital period is exactly 3/2 that of Neptune, which ensures that the conjunctions always occur near Pluto's aphelion. Long-term orbit integrations2-5 have uncovered other subtle resonances and near-resonances, and indicate that Pluto's orbit is chaotic yet remains macroscopically stable over billion-year timescales. A suggestion4 that the orbit may have evolved purely by chaotic dynamics appears unlikely in light of recent orbital stability studies6, unless one appeals to a well-timed collision to place Pluto in its stable orbit19. Here I show that Pluto could have acquired its current orbit during the late stages of planetary accretion, when the jovian planets underwent significant orbital migration as a result of encounters with residual planetesimals7. As Neptune moved outwards, a small body like Pluto in an initially circular orbit could have been captured into the 3:2 resonance, following which its orbital eccentricity would rise rapidly to its current Neptune-crossing value.",
author = "Renu Malhotra",
year = "1993",
month = "10",
day = "28",
language = "English (US)",
volume = "365",
journal = "Nature",
issn = "0028-0836",
publisher = "Nature Publishing Group",
number = "6449",

}

TY - JOUR

T1 - The origin of Pluto's peculiar orbit

AU - Malhotra, Renu

PY - 1993/10/28

Y1 - 1993/10/28

N2 - THE origin of Pluto's unusual orbit - the most eccentric and inclined of all the planets - remains a mystery. The orbits of Pluto and Neptune overlap, but close approaches of these two planets are prevented by the existence of a resonance condition1: Pluto's orbital period is exactly 3/2 that of Neptune, which ensures that the conjunctions always occur near Pluto's aphelion. Long-term orbit integrations2-5 have uncovered other subtle resonances and near-resonances, and indicate that Pluto's orbit is chaotic yet remains macroscopically stable over billion-year timescales. A suggestion4 that the orbit may have evolved purely by chaotic dynamics appears unlikely in light of recent orbital stability studies6, unless one appeals to a well-timed collision to place Pluto in its stable orbit19. Here I show that Pluto could have acquired its current orbit during the late stages of planetary accretion, when the jovian planets underwent significant orbital migration as a result of encounters with residual planetesimals7. As Neptune moved outwards, a small body like Pluto in an initially circular orbit could have been captured into the 3:2 resonance, following which its orbital eccentricity would rise rapidly to its current Neptune-crossing value.

AB - THE origin of Pluto's unusual orbit - the most eccentric and inclined of all the planets - remains a mystery. The orbits of Pluto and Neptune overlap, but close approaches of these two planets are prevented by the existence of a resonance condition1: Pluto's orbital period is exactly 3/2 that of Neptune, which ensures that the conjunctions always occur near Pluto's aphelion. Long-term orbit integrations2-5 have uncovered other subtle resonances and near-resonances, and indicate that Pluto's orbit is chaotic yet remains macroscopically stable over billion-year timescales. A suggestion4 that the orbit may have evolved purely by chaotic dynamics appears unlikely in light of recent orbital stability studies6, unless one appeals to a well-timed collision to place Pluto in its stable orbit19. Here I show that Pluto could have acquired its current orbit during the late stages of planetary accretion, when the jovian planets underwent significant orbital migration as a result of encounters with residual planetesimals7. As Neptune moved outwards, a small body like Pluto in an initially circular orbit could have been captured into the 3:2 resonance, following which its orbital eccentricity would rise rapidly to its current Neptune-crossing value.

UR - http://www.scopus.com/inward/record.url?scp=0027681059&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0027681059&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:0027681059

VL - 365

JO - Nature

JF - Nature

SN - 0028-0836

IS - 6449

ER -