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Volumn 329, Issue 5988, 2010, Pages 187-190

Capture of the sun's oort cloud from stars in its birth cluster

Author keywords

[No Author keywords available]

Indexed keywords

ASTRONOMY; CLOUD COVER; COMET; EXTRATERRESTRIAL MATTER; SOLAR SYSTEM;

EID: 77954574690     PISSN: 00368075     EISSN: 10959203     Source Type: Journal    
DOI: 10.1126/science.1187535     Document Type: Article
Times cited : (180)

References (33)
  • 2
    • 33144488056 scopus 로고    scopus 로고
    • M. C. Featou, K. U. Keller, H. A. Weaver, Eds. (Univ. of Arizona Press, Tucson, AZ)
    • L. Dones, P. R. Weissman, H. F. Levison, M. J. Duncan, in Comets II, M. C. Featou, K. U. Keller, H. A. Weaver, Eds. (Univ. of Arizona Press, Tucson, AZ, 2004), p. 153.
    • (2004) Comets II , pp. 153
    • Dones, L.1    Weissman, P.R.2    Levison, H.F.3    Duncan, M.J.4
  • 4
    • 77954602116 scopus 로고    scopus 로고
    • note
    • This basic picture does not change if we invoke a model in which the planets migrate substantially (24-26).
  • 5
    • 77954619623 scopus 로고    scopus 로고
    • The Sun was embedded in a star cluster for the first few million years of its existence. During this time, the gravitational potential of this cluster was the dominant perturber. After the Sun left the cluster, the Galaxy as a whole became the most important perturber
    • The Sun was embedded in a star cluster for the first few million years of its existence. During this time, the gravitational potential of this cluster was the dominant perturber. After the Sun left the cluster, the Galaxy as a whole became the most important perturber.
  • 6
    • 77954593377 scopus 로고    scopus 로고
    • note
    • 11.
  • 11
    • 77954591439 scopus 로고    scopus 로고
    • As suggested by figure 2 of (9)
    • As suggested by figure 2 of (9).
  • 12
    • 77954593376 scopus 로고    scopus 로고
    • This was varied from run to run in order to optimize processing time
    • This was varied from run to run in order to optimize processing time.
  • 13
    • 77954618534 scopus 로고    scopus 로고
    • We have placed the same number of comets around each star, independent of its mass. We took this simple approach because too little is known about other planetary systems to make a more physically based assumption. See SOM text 3 for a discussion and for results where we have relaxed our assumption
    • We have placed the same number of comets around each star, independent of its mass. We took this simple approach because too little is known about other planetary systems to make a more physically based assumption. See SOM text 3 for a discussion and for results where we have relaxed our assumption.
  • 14
    • 77954602660 scopus 로고    scopus 로고
    • Here we define a singleton as a star that is not gravitationally bound to either another star or to the cluster as a whole. The Sun is a singleton
    • Here we define a singleton as a star that is not gravitationally bound to either another star or to the cluster as a whole. The Sun is a singleton.
  • 15
    • 77954608785 scopus 로고    scopus 로고
    • The Oort cloud has been evolving and losing objects over the lifetime of the solar system. Thus, although the Oort cloud extends to a > ̃105 AU, we only included comets with a < 50,000 AU in our analysis in order to avoid the need to account for this loss. We chose 50,000 AU because this is the largest semimajor axis for which survival for 4 billion years is likely (2)
    • The Oort cloud has been evolving and losing objects over the lifetime of the solar system. Thus, although the Oort cloud extends to a > ̃105 AU, we only included comets with a < 50,000 AU in our analysis in order to avoid the need to account for this loss. We chose 50,000 AU because this is the largest semimajor axis for which survival for 4 billion years is likely (2)
  • 16
    • 77954590692 scopus 로고    scopus 로고
    • As we were preparing this manuscript,we became aware of (29), who independently found that this mechanism can be responsible for the formation of wide binary star systems
    • As we were preparing this manuscript, we became aware of (29), who independently found that this mechanism can be responsible for the formation of wide binary star systems.
  • 17
    • 77954576947 scopus 로고    scopus 로고
    • An encounter between the Sun and another star has been invoked before (30,31) to explain the origin of Sedna, which has an unusual orbit with a semimajor axis of 526 AU and a perihelion distance well beyond the orbits of the planets at 76 AU. See (32) for a detailed early study of this type of encounter
    • An encounter between the Sun and another star has been invoked before (30, 31) to explain the origin of Sedna, which has an unusual orbit with a semimajor axis of 526 AU and a perihelion distance well beyond the orbits of the planets at 76 AU. See (32) for a detailed early study of this type of encounter.
  • 18
    • 77954585837 scopus 로고    scopus 로고
    • In the real system, there are two dynamical mechanisms for stripping comets away from their original parent stars. The first involves close encounters between the stars. This effect is included in our calculations. The second is caused by close encounters between the comets and the planets in orbit around the parent stars. For computational reasons, this effect was not directly included in these calculations. However, because most comets are stripped by the first process in our simulations, the lack of the second is not significant from the dynamical point of view
    • In the real system, there are two dynamical mechanisms for stripping comets away from their original parent stars. The first involves close encounters between the stars. This effect is included in our calculations. The second is caused by close encounters between the comets and the planets in orbit around the parent stars. For computational reasons, this effect was not directly included in these calculations. However, because most comets are stripped by the first process in our simulations, the lack of the second is not significant from the dynamical point of view.
  • 21
    • 77954612584 scopus 로고    scopus 로고
    • The uncertainty in this value is over an order of magnitude. Here, we are simply using the classic value from (20)
    • The uncertainty in this value is over an order of magnitude. Here, we are simply using the classic value from (20).
  • 22
    • 77954578618 scopus 로고    scopus 로고
    • 16 g (20), which is very uncertain (21). Thus, it considers all possible sources for Oort cloud comets
    • 16 g (20), which is very uncertain (21). Thus, it considers all possible sources for Oort cloud comets.
  • 23
    • 77954603265 scopus 로고    scopus 로고
    • It is interesting to speculate whether we would expect to see substantial compositional differences between comets due to our results. These stars formed in the same cluster as the Sun, and thus all the comets formed basically from the same cloud of material. Thus, it is not obvious what to expect.
    • It is interesting to speculate whether we would expect to see substantial compositional differences between comets due to our results. These stars formed in the same cluster as the Sun, and thus all the comets formed basically from the same cloud of material. Thus, it is not obvious what to expect.
  • 33
    • 77954614201 scopus 로고    scopus 로고
    • We thank A. Morbidelli and L. Dones for useful discussions. This work was supported by NASA's Astrobiology Institute through a grant to the Goddard Center for Astrobiology. H.F.L. is grateful to NASA for funding through its Operational Support Services and Outer Planets Research programs. M.J.D. is grateful for the hospitality and financial support of the Isaac Newton Institute at Cambridge University, where some of this work was performed. M.J.D. acknowledges the continuing financial support of the Natural Sciences and Engineering Research Council, Canada. R.B. thanks Germany's Helmholz Alliance for financial support
    • We thank A. Morbidelli and L. Dones for useful discussions. This work was supported by NASA's Astrobiology Institute through a grant to the Goddard Center for Astrobiology. H.F.L. is grateful to NASA for funding through its Operational Support Services and Outer Planets Research programs. M.J.D. is grateful for the hospitality and financial support of the Isaac Newton Institute at Cambridge University, where some of this work was performed. M.J.D. acknowledges the continuing financial support of the Natural Sciences and Engineering Research Council, Canada. R.B. thanks Germany's Helmholz Alliance for financial support.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.