Skip to main content
SpringerLink
Log in

Against all odds? Forming the planet of the HD 196885 binary

  • Original Article
  • Published:
Celestial Mechanics and Dynamical Astronomy Aims and scope Submit manuscript

Abstract

HD 196885 Ab is the most “extreme” planet-in-a-binary discovered to date, whose orbit places it at the limit for orbital stability. The presence of a planet in such a highly perturbed region poses a clear challenge to planet-formation scenarios. We investigate this issue by focusing on the planet-formation stage that is arguably the most sensitive to binary perturbations: the mutual accretion of kilometre-sized planetesimals. To this effect we numerically estimate the impact velocities dv amongst a population of circumprimary planetesimals. We find that most of the circumprimary disc is strongly hostile to planetesimal accretion, especially the region around 2.6 AU (the planet’s location) where binary perturbations induce planetesimal-shattering dv of more than 1 kms−1. Possible solutions to the paradox of having a planet in such accretion-hostile regions are (1) that initial planetesimals were very big, at least 250 km (2) that the binary had an initial orbit at least twice the present one, and was later compacted due to early stellar encounters (3) that planetesimals did not grow by mutual impacts but by sweeping of dust (the “snowball” growth mode identified by Xie et al., in Astrophys J 724:1153, 2010b), or (4) that HD 196885 Ab was formed not by core-accretion but by the concurrent disc instability mechanism. All of these 4 scenarios remain however highly conjectural.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Similar content being viewed by others

References

  • Artymowicz P., Lubow S.H.: Dynamics of binary-disk interaction. 1: resonances and disk gap sizes. Astrophys. J. 421, 621 (1994)

    Article  ADS  Google Scholar 

  • Barbieri M., Marzari F., Scholl H.: Formation of terrestrial planets in close binary systems: the case of alpha Centauri A. Astron. Astrophys. 396, 219 (2002)

    Article  ADS  Google Scholar 

  • Beauge C., Leiva A.M., Haghighipour N., Otto J. C.: Dynamics of planetesimals due to gas drag from an eccentric precessing disc. Mon. Not. R. Astron. Soc. 408, 503 (2010)

    Article  ADS  Google Scholar 

  • Blum J., Wurm G.: The growth mechanisms of macroscopic bodies in protoplanetary disks. Annu. Rev. Astron. Astrophys. 46, 21 (2008)

    Article  ADS  Google Scholar 

  • Boley A.C.: The two modes of gas giant planet formation. Astrophys. J. 695, L53 (2009)

    Article  ADS  Google Scholar 

  • Boss A.P.: Gas giant protoplanets formed by disk instability in binary star systems. Astrophys. J. 641, 1148 (2006)

    Article  ADS  Google Scholar 

  • Chambers J.E.: Planetesimal formation by turbulent concentration. Icarus 208, 505 (2010)

    Article  ADS  Google Scholar 

  • Charnoz S., Thébault P., Brahic A.: Short-term collisional evolution of a disc perturbed by a giant-planet embryo. Astron. Astrophys. 373, 683 (2001)

    Article  ADS  Google Scholar 

  • Chauvin G., Lagrange A.-M., Udry S., Mayor M.: Characterization of the long-period companions of the exoplanet host stars: HD 196885, HD 1237 and HD 27442. VLT/NACO and SINFONI near-infrared, follow-up imaging and spectroscopy. Astron. Astrophys. 475, 723 (2007)

    Article  ADS  Google Scholar 

  • Chauvin G., Beust H., Lagrange A.-M., Eggenberger A.: Planetary systems in close binary stars: the case of HD 196885. Combined astrometric and radial velocity study. Astron. Astrophys. 528, 8 (2011)

    Article  ADS  Google Scholar 

  • Cieza L.A. et al.: Primordial circumstellar disks in binary systems: evidence for reduced lifetimes. Astrophys. J. 696, 84C (2009)

    Article  ADS  Google Scholar 

  • Correia A.C. et al.: The ELODIE survey for northern extra-solar planets. IV. HD 196885, a close binary star with a 3.7-year planet. Astron. Astrophys. 479, 271 (2008)

    Article  ADS  Google Scholar 

  • Cuzzi J. N., Hogan R. C., Shariff K.: Toward planetesimals: dense chondrule clumps in the protoplanetary nebula. Astrophys. J. 687, 1432 (2008)

    Article  ADS  Google Scholar 

  • Desidera S., Barbieri M.: Properties of planets in binary systems. The role of binary separation. Astron. Astrophys. 462, 345–353 (2007)

    Article  ADS  Google Scholar 

  • Duchêne G.: Planet formation in binary systems: a separation-dependent mechanism?. Astrophys. J. 709, L114 (2010)

    Article  ADS  Google Scholar 

  • Duquennoy A., Mayor M.: Multiplicity among solar-type stars in the solar neighbourhood. II—distribution of the orbital elements in an unbiased sample. Astron. Astrophys. 248, 485 (1991)

    ADS  Google Scholar 

  • Dvorak R., Pilat-Lohinger E., Funk B., Freistetter F.: Planets in habitable zones: a study of the binary Gamma Cephei. Astron. Astrophys. 398, L1 (2003)

    Article  ADS  Google Scholar 

  • Fragner M., Nelson R., Kley W.: On the dynamics and collisional growth of planetesimals in misaligned binary systems. Astron. Astrophys. 528, 40 (2011)

    Article  ADS  Google Scholar 

  • Goodchild S., Ogilvie G.: The dynamics of eccentric accretion discs in superhump systems. Mon. Not. R. Astron. Soc. 386, 973 (2006)

    Google Scholar 

  • Guedes J.M., Rivera E.J., Davis E., Laughlin G., Quintana E.V., Fischer D.A.: Formation and detectability of terrestrial planets around alpha Centauri B. J. Astrophys. 679, 1582 (2008)

    Article  ADS  Google Scholar 

  • Haghighipour N., Dvorak R., Pilat-Lohinger E.: Planetary dynamics and habitable planet formation in binary star systems. Astrophys. Space Sci. Lib. 366, 285 (2010)

    Article  ADS  Google Scholar 

  • Hale A.: Orbital coplanarity in solar-type binary systems: implications for planetary system formation and detection. Astron. J. 107, 306 (1994)

    Article  ADS  Google Scholar 

  • Hatzes A.P., Cochran W.D., Endl M., McArthur B., Paulson D.B., Walker G.A.H., Campbell B., Yang S.: A planetary companion to Gamma Cephei A. Astrophys. J. 599, 1383 (2003)

    Article  ADS  Google Scholar 

  • Hayashi C.: Structure of the Solar Nebula, growth and decay of magnetic fields and effects of magnetic and turbulent viscosities on the Nebula. Prog. Theor. Phys. Suppl. 70, 35 (1981)

    Article  ADS  Google Scholar 

  • Heppenheimer T.A.: On the formation of planets in binary star systems. Astron. Astrophys. 65, 421 (1978)

    ADS  Google Scholar 

  • Holman M.J., Wiegert P.A.: Long-term stability of planets in binary systems. Astron. J. 117, 621 (1999)

    Article  ADS  Google Scholar 

  • Jang-Condell H., Mugrauer M., Schmidt T.: Disk truncation and planet formation in gamma cephei. Astrophys. J. 683, L191 (2008)

    Article  ADS  Google Scholar 

  • Johansen A., Oishi J. S., Mac Low M.-M., Klahr H., Henning T., Youdin A.: Rapid planetesimal formation in turbulent circumstellar disks. Nature 448, 1022 (2007)

    Article  ADS  Google Scholar 

  • Kley W., Nelson R.P.: . In: Haghighipour, N. (eds) Planets in Binary Star Systems, Springer publishing company, Berlin (2007)

  • Kley W., Nelson R.P.: Planet formation in binary stars: the case of Gamma Cephei. Astron. Astrophys. 486, 617 (2008)

    Article  ADS  Google Scholar 

  • Kokubo E., Ida S.: Formation of protoplanets from planetesimals in the solar Nebula. Icarus 297, 1067 (2000)

    Google Scholar 

  • Lagrange A.-M., Beust H., Udry S., Chauvin G., Mayor M.: New constrains on gliese 86 B. VLT near infrared coronographic imaging survey of planetary hosts. Astron. Astrophys. 459, 955 (2006)

    Article  ADS  Google Scholar 

  • Lissauer J.J.: Planet formation. Annu. Rev. Astron. Astrophys. 31, 129 (1993)

    Article  ADS  Google Scholar 

  • Lithwick Y., Chiang E.: Collisional particle disks. Astrophys. J. 656, 524 (2007)

    Article  ADS  Google Scholar 

  • Makino J., Fukushige T., Funato Y., Kokubo E.: On the mass distribution of planetesimals in the early runaway stage. New Astron. 3, 411 (1998)

    Article  ADS  Google Scholar 

  • Malmberg D., Davies M.B., Chambers J.E.: Close encounters in young stellar clusters: implications for planetary systems in the solar neighbourhood. Mon. Not. R. Astron. Soc. 378, 1207 (2007)

    Article  ADS  Google Scholar 

  • Marzari F., Scholl H.: Planetesimal accretion in binary star systems. Astrophy. J. 543, 328 (2000)

    Article  ADS  Google Scholar 

  • Marzari F., Thebault P., Scholl H.: Planetesimal evolution in circumbinary gaseous disks: a hybrid model. Astrophys. J. 681, 1599 (2008)

    Article  ADS  Google Scholar 

  • Mayer L., Wadsley J., Quinn T., Stadel J.: Gravitational instability in binary protoplanetary discs: new constraints on giant planet formation. Mon. Not. R. Astron. Soc. 363, 641 (2005)

    Article  ADS  Google Scholar 

  • Minton D. A., Malhotra R.: Dynamical erosion of the asteroid belt and implications for large impacts in the inner solar system. Icarus 207, 744 (2010)

    Article  ADS  Google Scholar 

  • Morbidelli A., Bottke W.F., Nesvorný D., Levison H.F.: Asteroids were born big. Icarus 204, 558 (2009)

    Article  ADS  Google Scholar 

  • Mugrauer M., Neuhäuser R.: The multiplicity of exoplanet host stars. New low-mass stellar companions of the exoplanet host stars HD 125612 and HD 212301. Astron. Astrophys. 494, 373 (2009)

    Article  ADS  Google Scholar 

  • Nelson A.: Planet formation is unlikely in equal-mass binary systems with a = 50 AU. Astrophys. J. 537, 65 (2000)

    Article  ADS  Google Scholar 

  • Neuhäuser R., Mugrauer M., Fukagawa M., Torres G., Schmidt T.: Direct detection of exoplanet host star companion Gamma Cep B and revised masses for both stars and the sub-stellar object. Astron. Astrophys. 462, 777 (2007)

    Article  ADS  Google Scholar 

  • Paardekooper S.-J., Thébault P., Mellema G.: Planetesimal and gas dynamics in binaries. Mon. Not. R. Astron. Soc. 386, 973 (2008)

    Article  ADS  Google Scholar 

  • Paardekooper S.-J., Leinhardt Z.M.: Planetesimal collisions in binary systems. Mon. Not. R. Astron. Soc. 403, L64 (2010)

    Article  ADS  Google Scholar 

  • Payne M.J., Wyatt M.C., Thebault P.: Outward migration of terrestrial embryos in binary systems. Mon. Not. R. Astron. Soc. 400, 1936 (2009)

    Article  ADS  Google Scholar 

  • Plavchan P., Werner M.W., Chen C.H., Stapelfeldt K.R., Su K.Y.L., Stauffer J.R., Song I.: New debris disks around young, low-mass stars discovered with the Spitzer Space Telescope. Astrophys. J. 698, 1068 (2009)

    Article  ADS  Google Scholar 

  • Queloz D., Mayor M., Weber L., Blécha A., Burnet M., Confino B., Naef D., Pepe F., Santos N., Udry S.: The CORALIE survey for southern extra-solar planets. I. A planet orbiting the star Gliese 86. Astron. Astrophys. 354, 99 (2000)

    ADS  Google Scholar 

  • Quintana E.V., Adams F.C., Lissauer J.J., Chambers J.E.: Terrestrial planet formation around individual stars within binary systems. Astrophys. J. 660, 807 (2007)

    Article  ADS  Google Scholar 

  • Savonije G.J., Papaloizou J.C.B., Lin D.N.C.: On tidally induced shocks in accretion discs in close binary systems. Mon. Not. R. Astron. Soc. 268, 13 (1994)

    ADS  Google Scholar 

  • Stewart S. T., Leinhardt Z. M.: Velocity-dependent catastrophic disruption criteria for planetesimals. Astrophy. J. 691, L133 (2009)

    Article  ADS  Google Scholar 

  • Takeuchi T., Lin D.N.C.: Radial flow of dust particles in accretion disks. Astrophys. J. 581, 1344 (2002)

    Article  ADS  Google Scholar 

  • Teiser J.W., Wurm G.: High-velocity dust collisions: forming planetesimals in a fragmentation cascade with final accretion. Mon. Not. R. Astron. Soc. 393, 1584 (2009)

    Article  ADS  Google Scholar 

  • Thébault P., Augereau J.C.: Collisional processes and size distribution in spatially extended debris discs. Astron. Astrophys. 472, 169 (2007)

    Article  ADS  Google Scholar 

  • Thébault P., Brahic A.: Dynamical influence of a proto-Jupiter on a disc of colliding planetesimals. Planet. space sci. 47, 233 (1998)

    Article  ADS  Google Scholar 

  • Thébault P., Marzari F., Scholl H.: Relative velocities among accreting planetesimals in binary systems: The circumprimary case. Icarus 183, 193 (2006)

    Article  ADS  Google Scholar 

  • Thébault P., Marzari F., Scholl H., Turrini D., Barbieri M.: Planetary formation in the Gamma Cephei system. Astron. Astrophys. 427, 1097 (2004)

    Article  ADS  Google Scholar 

  • Thébault P., Marzari F., Scholl H.: Planet formation in alpha centauri a revisited: not so accretion friendly after all. Mon. Not. R. Astron. Soc. 388, 1528 (2008)

    Article  ADS  Google Scholar 

  • Thébault P., Marzari F., Scholl H.: Planet formation in the habitable zone of alpha Centauri B. Mon. Not. R. Astron. Soc. 393, L21 (2009)

    Article  ADS  Google Scholar 

  • Weidenschilling S., Davis D.R.: Orbital resonances in the solar nebula—implications for planetary accretion. Icarus 62, 16 (1985)

    Article  ADS  Google Scholar 

  • Xie J.-W., Zhou J.-L.: Planetesimal accretion in binary systems: the effects of gas dissipation. Astrophys. J. 686, 570 (2008)

    Article  ADS  Google Scholar 

  • Xie J.-W., Zhou J.-L.: Planetesimal accretion in binary systems: role of the companion’s orbital inclination. Astrophys. J. 698, 2066 (2009)

    Article  ADS  Google Scholar 

  • Xie J.-W., Zhou J.-L., Ge J.: Planetesimal accretion in binary systems: could planets form around alpha Centauri B?. Astrophys. J. 708, 1566 (2010a)

    Article  ADS  Google Scholar 

  • Xie J.-W., Payne M. J., Thebault P., Zhou J.-L., Ge J.: From dust to planetesimal: the snowball phase?. Astrophys. J. 724, 1153 (2010b)

    Article  ADS  Google Scholar 

  • Zsom A., Sandor Z., Dullemond C.: The first stages of planet formation in binary systems: how far can dust coagulation proceed?. Astron. Astrophys. 527, 10 (2011)

    Article  ADS  Google Scholar 

  • Zucker S., Mazeh T., Santos N.C., Udry S., Mayor M.: Multi-order TODCOR: application to observations taken with the CORALIE echelle spectrograph. II. A planet in the system HD 41004. Astron. Astrophys. 426, 695 (2004)

    Article  ADS  Google Scholar 

Download references

Author information

Authors and Affiliations

  1. LESIA, Observatoire de Paris, Meudon Principal Cedex, 92195, France

    P. Thebault

Authors
  1. P. Thebault
    View author publications

    You can also search for this author in PubMed Google Scholar

Corresponding author

Correspondence to P. Thebault.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Thebault, P. Against all odds? Forming the planet of the HD 196885 binary. Celest Mech Dyn Astr 111, 29–49 (2011). https://doi.org/10.1007/s10569-011-9346-2

Download citation

  • Received:

  • Revised:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10569-011-9346-2

Keywords

Search

Navigation