The effects of fly-bys on planetary systems
(2011) In Monthly Notices of the Royal Astronomical Society 411(2). p.859-877- Abstract
- Most of the observed extrasolar planets are found on tight and often eccentric orbits. The high eccentricities are not easily explained by planet-formation models, which predict that planets should be on rather circular orbits. Here we explore whether fly-bys involving planetary systems with properties similar to those of the gas giants in the Solar system can produce planets with properties similar to the observed planets. Using numerical simulations, we show that fly-bys can cause the immediate ejection of planets, and sometimes also lead to the capture of one or more planets by the intruder. More common, however, is that fly-bys only perturb the orbits of planets, sometimes leaving the system in an unstable state. Over time-scales of a... (More)
- Most of the observed extrasolar planets are found on tight and often eccentric orbits. The high eccentricities are not easily explained by planet-formation models, which predict that planets should be on rather circular orbits. Here we explore whether fly-bys involving planetary systems with properties similar to those of the gas giants in the Solar system can produce planets with properties similar to the observed planets. Using numerical simulations, we show that fly-bys can cause the immediate ejection of planets, and sometimes also lead to the capture of one or more planets by the intruder. More common, however, is that fly-bys only perturb the orbits of planets, sometimes leaving the system in an unstable state. Over time-scales of a few million to several hundred million years after the fly-by, this perturbation can trigger planet-planet scatterings, leading to the ejection of one or more planets. For example, in the case of the four gas giants of the Solar system, the fraction of systems from which at least one planet is ejected more than doubles in 108 yr after the fly-by. The remaining planets are often left on more eccentric orbits, similar to the eccentricities of the observed extrasolar planets. We combine our results of how fly-bys affect Solar-system-like planetary systems, with the rate at which encounters in young stellar clusters occur. For example, we measure the effects of fly-bys on the four gas giants in the Solar system. We find, that for such systems, between 5 and 15 per cent suffer ejections of planets in 108 yr after fly-bys in typical open clusters. Thus, encounters in young stellar clusters can significantly alter the properties of any planets orbiting stars in clusters. As a large fraction of stars which populate the solar neighbourhood form in stellar clusters, encounters can significantly affect the properties of the observed extrasolar planets. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/1869014
- author
- Malmberg, Daniel LU ; Davies, Melvyn B LU and Heggie, Douglas C.
- organization
- publishing date
- 2011
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- celestial mechanics, planet-star interactions, stars: kinematics and, dynamics, planetary systems, open clusters and associations: general
- in
- Monthly Notices of the Royal Astronomical Society
- volume
- 411
- issue
- 2
- pages
- 859 - 877
- publisher
- Oxford University Press
- external identifiers
-
- wos:000286988800010
- scopus:79551587734
- ISSN
- 1365-2966
- DOI
- 10.1111/j.1365-2966.2010.17730.x
- language
- English
- LU publication?
- yes
- id
- 62316ca5-eac9-4463-8046-e86f4d2a80b4 (old id 1869014)
- date added to LUP
- 2016-04-01 10:21:33
- date last changed
- 2024-04-07 07:56:26
@article{62316ca5-eac9-4463-8046-e86f4d2a80b4,
abstract = {{Most of the observed extrasolar planets are found on tight and often eccentric orbits. The high eccentricities are not easily explained by planet-formation models, which predict that planets should be on rather circular orbits. Here we explore whether fly-bys involving planetary systems with properties similar to those of the gas giants in the Solar system can produce planets with properties similar to the observed planets. Using numerical simulations, we show that fly-bys can cause the immediate ejection of planets, and sometimes also lead to the capture of one or more planets by the intruder. More common, however, is that fly-bys only perturb the orbits of planets, sometimes leaving the system in an unstable state. Over time-scales of a few million to several hundred million years after the fly-by, this perturbation can trigger planet-planet scatterings, leading to the ejection of one or more planets. For example, in the case of the four gas giants of the Solar system, the fraction of systems from which at least one planet is ejected more than doubles in 108 yr after the fly-by. The remaining planets are often left on more eccentric orbits, similar to the eccentricities of the observed extrasolar planets. We combine our results of how fly-bys affect Solar-system-like planetary systems, with the rate at which encounters in young stellar clusters occur. For example, we measure the effects of fly-bys on the four gas giants in the Solar system. We find, that for such systems, between 5 and 15 per cent suffer ejections of planets in 108 yr after fly-bys in typical open clusters. Thus, encounters in young stellar clusters can significantly alter the properties of any planets orbiting stars in clusters. As a large fraction of stars which populate the solar neighbourhood form in stellar clusters, encounters can significantly affect the properties of the observed extrasolar planets.}},
author = {{Malmberg, Daniel and Davies, Melvyn B and Heggie, Douglas C.}},
issn = {{1365-2966}},
keywords = {{celestial mechanics; planet-star interactions; stars: kinematics and; dynamics; planetary systems; open clusters and associations: general}},
language = {{eng}},
number = {{2}},
pages = {{859--877}},
publisher = {{Oxford University Press}},
series = {{Monthly Notices of the Royal Astronomical Society}},
title = {{The effects of fly-bys on planetary systems}},
url = {{http://dx.doi.org/10.1111/j.1365-2966.2010.17730.x}},
doi = {{10.1111/j.1365-2966.2010.17730.x}},
volume = {{411}},
year = {{2011}},
}