Abstract
The Solar System includes two planets—Mercury and Mars—significantly less massive than Earth, and all evidence indicates that planets of similar size orbit many stars. In fact, one of the first exoplanets to be discovered is a lunar-mass planet around a millisecond pulsar. Novel classes of exoplanets have inspired new ideas about planet formation and evolution, and these “sub-Earths” should be no exception: they include planets with masses between Mars and Venus for which there are no Solar System analogs. Advances in astronomical instrumentation and recent space missions have opened the sub-Earth frontier for exploration: the Kepler mission has discovered dozens of confirmed or candidate sub-Earths transiting their host stars. It can detect Mars-size planets around its smallest stellar targets, as well as exomoons of comparable size. Although the application of the Doppler method is currently limited by instrument stability, future spectrographs may detect equivalent planets orbiting close to nearby bright stars. Future space-based microlensing missions should be able to probe the sub-Earth population on much wider orbits. A census of sub-Earths will complete the reconnaissance of the exoplanet mass spectrum and test predictions of planet formation models, including whether low-mass M dwarf stars preferentially host the smallest planets. The properties of sub-Earths may reflect their low gravity, diverse origins, and environment, but they will be elusive: Observations of eclipsing systems by the James Webb Space Telescope may give us our first clues to the properties of these small worlds.
Similar content being viewed by others
Notes
We discuss large satellites of exoplanets, or “exomoons” in Sect. 4.3.
The extended mission has been terminated due to the failure of a second reaction wheel on the spacecraft.
References
C.B. Agnor, D.P. Hamilton, Neptune’s capture of its moon Triton in a binary-planet gravitational encounter. Nature 441, 192–194 (2006). doi:10.1038/nature04792
E. Agol, J. Steffen, R. Sari, W. Clarkson, On detecting terrestrial planets with timing of giant planet transits. Mon. Not. R. Astron. Soc. 359, 567–579 (2005). doi:10.1111/j.1365-2966.2005.08922.x
T.J. Ahrens, Impact erosion of terrestrial planetary atmospheres. Annu. Rev. Earth Planet. Sci. 21, 525–555 (1993). doi:10.1146/annurev.ea.21.050193.002521
S.M. Andrews, K.A. Rosenfeld, A.L. Kraus, D.J. Wilner, The mass dependence between protoplanetary disks and their stellar hosts. Astrophys. J. 771, 129 (2013). doi:10.1088/0004-637X/771/2/129
M. Bailes, S.D. Bates, V. Bhalerao, N.D.R. Bhat, M. Burgay, S. Burke-Spolaor, N. D’Amico, S. Johnston, M.J. Keith, M. Kramer, S.R. Kulkarni, L. Levin, A.G. Lyne, S. Milia, A. Possenti, L. Spitler, B. Stappers, W. van Straten, Transformation of a star into a planet in a millisecond pulsar binary. Science 333, 1717 (2011). doi:10.1126/science.1208890
T. Barclay, J.F. Rowe, J.J. Lissauer, D. Huber, F. Fressin, S.B. Howell, S.T. Bryson, W.J. Chaplin, J.-M. Désert, E.D. Lopez, G.W. Marcy, F. Mullally, D. Ragozzine, G. Torres, E.R. Adams, E. Agol, D. Barrado, S. Basu, T.R. Bedding, L.A. Buchhave, D. Charbonneau, J.L. Christiansen, J. Christensen-Dalsgaard, D. Ciardi, W.D. Cochran, A.K. Dupree, Y. Elsworth, M. Everett, D.A. Fischer, E.B. Ford, J.J. Fortney, J.C. Geary, M.R. Haas, R. Handberg, S. Hekker, C.E. Henze, E. Horch, A.W. Howard, R.C. Hunter, H. Isaacson, J.M. Jenkins, C. Karoff, S.D. Kawaler, H. Kjeldsen, T.C. Klaus, D.W. Latham, J. Li, J. Lillo-Box, M.N. Lund, M. Lundkvist, T.S. Metcalfe, A. Miglio, R.L. Morris, E.V. Quintana, D. Stello, J.C. Smith, M. Still, S.E. Thompson, A sub-Mercury-sized exoplanet. Nature 494, 452–454 (2013). doi:10.1038/nature11914
R. Barry, J. Kruk, J. Anderson, J.-P. Beaulieu, D.P. Bennett, J. Catanzarite, E. Cheng, S. Gaudi, N. Gehrels, S. Kane, J. Lunine, T. Sumi, A. Tanner, W. Traub, The exoplanet microlensing survey by the proposed WFIRST observatory, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 8151 (2011). doi:10.1117/12.898574
N.M. Batalha, J.F. Rowe, S.T. Bryson, T. Barclay, C.J. Burke, D.A. Caldwell, J.L. Christiansen, F. Mullally, S.E. Thompson, T.M. Brown, A.K. Dupree, D.C. Fabrycky, E.B. Ford, J.J. Fortney, R.L. Gilliland, H. Isaacson, D.W. Latham, G.W. Marcy, S.N. Quinn, D. Ragozzine, A. Shporer, W.J. Borucki, D.R. Ciardi, T.N. Gautier III, M.R. Haas, J.M. Jenkins, D.G. Koch, J.J. Lissauer, W. Rapin, G.S. Basri, A.P. Boss, L.A. Buchhave, J.A. Carter, D. Charbonneau, J. Christensen-Dalsgaard, B.D. Clarke, W.D. Cochran, B. Demory, J. Desert, E. Devore, L.R. Doyle, G.A. Esquerdo, M. Everett, F. Fressin, J.C. Geary, F.R. Girouard, A. Gould, J.R. Hall, M.J. Holman, A.W. Howard, S.B. Howell, K.A. Ibrahim, K. Kinemuchi, H. Kjeldsen, T.C. Klaus, J. Li, P.W. Lucas, S. Meibom, R.L. Morris, A. Prša, E. Quintana, D.T. Sanderfer, D. Sasselov, S.E. Seader, J.C. Smith, J.H. Steffen, M. Still, M.C. Stumpe, J.C. Tarter, P. Tenenbaum, G. Torres, J.D. Twicken, K. Uddin, J. Van Cleve, L. Walkowicz, W.F. Welsh, Planetary candidates observed by Kepler. III. Analysis of the first 16 months of data. Astrophys. J. Suppl. Ser. 204, 24 (2013). doi:10.1088/0067-0049/204/2/24
J.L. Bean, A. Seifahrt, H. Hartman, H. Nilsson, G. Wiedemann, A. Reiners, S. Dreizler, T.J. Henry, The CRIRES search for planets around the lowest-mass stars. I. High-precision near-infrared radial velocities with an ammonia gas cell. Astrophys. J. 713, 410–422 (2010). doi:10.1088/0004-637X/713/1/410
D.P. Bennett, in Detection of Extrasolar Planets by Gravitational Microlensing, ed. by J.W. Mason (Praxis Publishing, Athens, 2008), p. 47. doi:10.1007/978-3-540-74008-7-3
D.P. Bennett, S.H. Rhie, Detecting Earth-mass planets with gravitational microlensing. Astrophys. J. 472, 660 (1996). doi:10.1086/178096
D.P. Bennett, S.H. Rhie, Simulation of a space-based microlensing survey for terrestrial extrasolar planets. Astrophys. J. 574, 985–1003 (2002). doi:10.1086/340977
W. Benz, W.L. Slattery, A.G.W. Cameron, Collisional stripping of Mercury’s mantle. Icarus 74, 516–528 (1988). doi:10.1016/0019-1035(88)90118-2
W. Benz, A. Anic, J. Horner, J.A. Whitby, The origin of Mercury. Space Sci. Rev. 132, 189–202 (2007). doi:10.1007/s11214-007-9284-1
J. Blum, G. Wurm, Experiments on sticking, restructuring, and fragmentation of preplanetary dust aggregates. Icarus 143, 138–146 (2000). doi:10.1006/icar.1999.6234
W.J. Borucki, D. Koch, G. Basri, N. Batalha, T. Brown, D. Caldwell, J. Caldwell, J. Christensen-Dalsgaard, W.D. Cochran, E. DeVore, E.W. Dunham, A.K. Dupree, T.N. Gautier, J.C. Geary, R. Gilliland, A. Gould, S.B. Howell, J.M. Jenkins, Y. Kondo, D.W. Latham, G.W. Marcy, S. Meibom, H. Kjeldsen, J.J. Lissauer, D.G. Monet, D. Morrison, D. Sasselov, J. Tarter, A. Boss, D. Brownlee, T. Owen, D. Buzasi, D. Charbonneau, L. Doyle, J. Fortney, E.B. Ford, M.J. Holman, S. Seager, J.H. Steffen, W.F. Welsh, J. Rowe, H. Anderson, L. Buchhave, D. Ciardi, L. Walkowicz, W. Sherry, E. Horch, H. Isaacson, M.E. Everett, D. Fischer, G. Torres, J.A. Johnson, M. Endl, P. MacQueen, S.T. Bryson, J. Dotson, M. Haas, J. Kolodziejczak, J. Van Cleve, H. Chandrasekaran, J.D. Twicken, E.V. Quintana, B.D. Clarke, C. Allen, J. Li, H. Wu, P. Tenenbaum, E. Verner, F. Bruhweiler, J. Barnes, A. Prsa, Kepler planet-detection mission: introduction and first results. Science 327, 977 (2010). doi:10.1126/science.1185402
W.J. Borucki, D.G. Koch, G. Basri, N. Batalha, T.M. Brown, S.T. Bryson, D. Caldwell, J. Christensen-Dalsgaard, W.D. Cochran, E. DeVore, E.W. Dunham, T.N. Gautier III, J.C. Geary, R. Gilliland, A. Gould, S.B. Howell, J.M. Jenkins, D.W. Latham, J.J. Lissauer, G.W. Marcy, J. Rowe, D. Sasselov, A. Boss, D. Charbonneau, D. Ciardi, L. Doyle, A.K. Dupree, E.B. Ford, J. Fortney, M.J. Holman, S. Seager, J.H. Steffen, J. Tarter, W.F. Welsh, C. Allen, L.A. Buchhave, J.L. Christiansen, B.D. Clarke, S. Das, J.-M. Désert, M. Endl, D. Fabrycky, F. Fressin, M. Haas, E. Horch, A. Howard, H. Isaacson, H. Kjeldsen, J. Kolodziejczak, C. Kulesa, J. Li, P.W. Lucas, P. Machalek, D. McCarthy, P. MacQueen, S. Meibom, T. Miquel, A. Prsa, S.N. Quinn, E.V. Quintana, D. Ragozzine, W. Sherry, A. Shporer, P. Tenenbaum, G. Torres, J.D. Twicken, J. Van Cleve, L. Walkowicz, F.C. Witteborn, M. Still, Characteristics of planetary candidates observed by Kepler. II. Analysis of the first four months of data. Astrophys. J. 736, 19 (2011). doi:10.1088/0004-637X/736/1/19
W.J. Borucki, E. Agol, F. Fressin, L. Kaltenegger, J. Rowe, H. Isaacson, D. Fischer, N. Batalha, J.J. Lissauer, G.W. Marcy, D. Fabrycky, J.-M. Désert, S.T. Bryson, T. Barclay, F. Bastien, A. Boss, E. Brugamyer, L.A. Buchhave, C. Burke, D.A. Caldwell, J. Carter, D. Charbonneau, J.R. Crepp, J. Christensen-Dalsgaard, J.L. Christiansen, D. Ciardi, W.D. Cochran, E. DeVore, L. Doyle, A.K. Dupree, M. Endl, M.E. Everett, E.B. Ford, J. Fortney, T.N. Gautier, J.C. Geary, A. Gould, M. Haas, C. Henze, A.W. Howard, S.B. Howell, D. Huber, J.M. Jenkins, H. Kjeldsen, R. Kolbl, J. Kolodziejczak, D.W. Latham, B.L. Lee, E. Lopez, F. Mullally, J.A. Orosz, A. Prsa, E.V. Quintana, R. Sanchis-Ojeda, D. Sasselov, S. Seader, A. Shporer, J.H. Steffen, M. Still, P. Tenenbaum, S.E. Thompson, G. Torres, J.D. Twicken, W.F. Welsh, J.N. Winn, Kepler-62: a five-planet system with planets of 1.4 and 1.6 Earth radii in the habitable zone. Science 340, 587–590 (2013). doi:10.1126/science.1234702
F. Bouchy, R.F. Díaz, G. Hébrard, L. Arnold, I. Boisse, X. Delfosse, S. Perruchot, A. Santerne, SOPHIE+: first results of an octagonal-section fiber for high-precision radial velocity measurements. Astron. Astrophys. 549, 49 (2013). doi:10.1051/0004-6361/201219979
T.M. Brown, D. Charbonneau, R.L. Gilliland, R.W. Noyes, A. Burrows, Hubble space telescope time-series photometry of the transiting planet of HD 209458. Astrophys. J. 552, 699–709 (2001). doi:10.1086/320580
T.M. Brown, D.W. Latham, M.E. Everett, G.A. Esquerdo, Kepler input catalog: photometric calibration and stellar classification. Astron. J. 142, 112 (2011). doi:10.1088/0004-6256/142/4/112
L.A. Buchhave, D.W. Latham, A. Johansen, M. Bizzarro, G. Torres, J.F. Rowe, N.M. Batalha, W.J. Borucki, E. Brugamyer, C. Caldwell, S.T. Bryson, D.R. Ciardi, W.D. Cochran, M. Endl, G.A. Esquerdo, E.B. Ford, J.C. Geary, R.L. Gilliland, T. Hansen, H. Isaacson, J.B. Laird, P.W. Lucas, G.W. Marcy, J.A. Morse, P. Robertson, A. Shporer, R.P. Stefanik, M. Still, S.N. Quinn, An abundance of small exoplanets around stars with a wide range of metallicities. Nature 486, 375–377 (2012). doi:10.1038/nature11121
R.P. Butler, G.W. Marcy, E. Williams, C. McCarthy, P. Dosanjh, S.S. Vogt, Attaining Doppler precision of 3 M s-1. Publ. Astron. Soc. Pac. 108, 500 (1996). doi:10.1086/133755
R.P. Butler, C.G. Tinney, G.W. Marcy, H.R.A. Jones, A.J. Penny, K. Apps, Two new planets from the Anglo-Australian planet search. Astrophys. J. 555, 410–417 (2001). doi:10.1086/321467
A.G.W. Cameron, The partial volatilization of Mercury. Icarus 64, 285–294 (1985). doi:10.1016/0019-1035(85)90091-0
R.M. Canup, W.R. Ward, A common mass scaling for satellite systems of gaseous planets. Nature 441, 834–839 (2006). doi:10.1038/nature04860
J. Chambers, A semi-analytic model for oligarchic growth. Icarus 180, 496–513 (2006). doi:10.1016/j.icarus.2005.10.017
S. Charpinet, G. Fontaine, P. Brassard, E.M. Green, V. Van Grootel, S.K. Randall, R. Silvotti, A.S. Baran, R.H. Østensen, S.D. Kawaler, J.H. Telting, A compact system of small planets around a former red-giant star. Nature 480, 496–499 (2011). doi:10.1038/nature10631
E. Chiang, G. Laughlin, The minimum-mass extrasolar nebula: in-situ formation of close-in super-Earths. Mon. Not. R. Astron. Soc. 431, 3444 (2013). doi:10.1093/mnras/stt424
E. Chiang, A.N. Youdin, Forming planetesimals in solar and extrasolar nebulae. Annu. Rev. Earth Planet. Sci. 38, 493–522 (2010). doi:10.1146/annurev-earth-040809-152513
M.C. Clampin, Status of the James Webb space telescope observatory, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 8442 (2012). doi:10.1117/12.926429
K.D. Colón, E.B. Ford, R.C. Morehead, Constraining the false positive rate for Kepler planet candidates with multicolour photometry from the GTC. Mon. Not. R. Astron. Soc. 426, 342–353 (2012). doi:10.1111/j.1365-2966.2012.21711.x
R. Cosentino, C. Lovis, F. Pepe, A. Collier Cameron, D.W. Latham, E. Molinari, S. Udry, N. Bezawada, M. Black, A. Born, N. Buchschacher, D. Charbonneau, P. Figueira, M. Fleury, A. Galli, A. Gallie, X. Gao, A. Ghedina, C. Gonzalez, M. Gonzalez, J. Guerra, D. Henry, K. Horne, I. Hughes, D. Kelly, M. Lodi, D. Lunney, C. Maire, M. Mayor, G. Micela, M.P. Ordway, J. Peacock, D. Phillips, G. Piotto, D. Pollacco, D. Queloz, K. Rice, C. Riverol, L. Riverol, J. San Juan, D. Sasselov, D. Segransan, A. Sozzetti, D. Sosnowska, B. Stobie, A. Szentgyorgyi, A. Vick, L. Weber, Harps-N: the new planet hunter at TNG, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 8446 (2012). doi:10.1117/12.925738
N.B. Cowan, E. Agol, The statistics of Albedo and heat recirculation on hot exoplanets. Astrophys. J. 729, 54 (2011). doi:10.1088/0004-637X/729/1/54
A.N. Cox, C.A. Pilachowski, Allen’s astrophysical quantities. Phys. Today 53(10), 100000 (2000). doi:10.1063/1.1325201
M. Ćuk, J.A. Burns, On the secular behavior of irregular satellites. Astron. J. 128, 2518–2541 (2004). doi:10.1086/424937
A. Dalgarno, F.J. Smith, The thermal conductivity and viscosity of atomic oxygen. Planet. Space Sci. 9, 1 (1962). doi:10.1016/0032-0633(62)90064-8
B.-O. Demory, M. Gillon, S. Seager, B. Benneke, D. Deming, B. Jackson, Detection of thermal emission from a super-Earth. Astrophys. J. Lett. 751, 28 (2012). doi:10.1088/2041-8205/751/2/L28
A. Dressler, D. Spergel, M. Mountain, M. Postman, E. Elliott, E. Bendek, D. Bennett, J. Dalcanton, S. Gaudi, N. Gehrels, O. Guyon, C. Hirata, J. Kalirai, N.J. Kasdin, J. Kruk, B. Macintosh, S. Malhotra, M. Penny, S. Perlmutter, G. Rieke, A. Riess, J. Rhoads, S. Shaklan, R. Somerville, D. Stern, R. Thompson, D. Weinberg, Exploring the NRO opportunity for a Hubble-sized wide-field near-IR space telescope—NEW WFIRST (2012). arXiv e-prints
X. Dumusque, S. Udry, C. Lovis, N.C. Santos, M.J.P.F.G. Monteiro, Planetary detection limits taking into account stellar noise. I. Observational strategies to reduce stellar oscillation and granulation effects. Astron. Astrophys. 525, 140 (2011). doi:10.1051/0004-6361/201014097
X. Dumusque, F. Pepe, C. Lovis, D. Ségransan, J. Sahlmann, W. Benz, F. Bouchy, M. Mayor, D. Queloz, N. Santos, S. Udry, An Earth-mass planet orbiting α Centauri B. Nature 491, 207–211 (2012). doi:10.1038/nature11572
D.S. Ebel, C.M.O. Alexander, Equilibrium condensation from chondritic porous IDP enriched vapor: implications for Mercury and enstatite chondrite origins. Planet. Space Sci. 59, 1888–1894 (2011). doi:10.1016/j.pss.2011.07.017
S. Elser, B. Moore, J. Stadel, R. Morishima, How common are Earth-Moon planetary systems? Icarus 214, 357–365 (2011). doi:10.1016/j.icarus.2011.05.025
M. Endl, M. Kürster, S. Els, The planet search program at the ESO Coudé Echelle spectrometer. I. Data modeling technique and radial velocity precision tests. Astron. Astrophys. 362, 585–594 (2000)
B. Fegley, A.G.W. Cameron, A vaporization model for iron/silicate fractionation in the Mercury protoplanet. Earth Planet. Sci. Lett. 82, 207–222 (1987). doi:10.1016/0012-821X(87)90196-8
M.J. Fogg, R.P. Nelson, The effect of type I migration on the formation of terrestrial planets in hot-Jupiter systems. Astron. Astrophys. 472, 1003–1015 (2007). doi:10.1051/0004-6361:20077950
E.B. Ford, J.F. Rowe, D.C. Fabrycky, J.A. Carter, M.J. Holman, J.J. Lissauer, D. Ragozzine, J.H. Steffen, N.M. Batalha, W.J. Borucki, S. Bryson, D.A. Caldwell, E.W. Dunham, T.N. Gautier III, J.M. Jenkins, D.G. Koch, J. Li, P. Lucas, G.W. Marcy, S. McCauliff, F.R. Mullally, E. Quintana, M. Still, P. Tenenbaum, S.E. Thompson, J.D. Twicken, Transit timing observations from Kepler. I. Statistical analysis of the first four months. Astrophys. J. Suppl. Ser. 197, 2 (2011). doi:10.1088/0067-0049/197/1/2
F. Fressin, G. Torres, J.F. Rowe, D. Charbonneau, L.A. Rogers, S. Ballard, N.M. Batalha, W.J. Borucki, S.T. Bryson, L.A. Buchhave, D.R. Ciardi, J.-M. Désert, C.D. Dressing, D.C. Fabrycky, E.B. Ford, T.N. Gautier III, C.E. Henze, M.J. Holman, A. Howard, S.B. Howell, J.M. Jenkins, D.G. Koch, D.W. Latham, J.J. Lissauer, G.W. Marcy, S.N. Quinn, D. Ragozzine, D.D. Sasselov, S. Seager, T. Barclay, F. Mullally, S.E. Seader, M. Still, J.D. Twicken, S.E. Thompson, K. Uddin, Two earth-sized planets orbiting Kepler-20. Nature 482, 195–198 (2012). doi:10.1038/nature10780
F. Fressin, G. Torres, D. Charbonneau, S.T. Bryson, J. Christiansen, C.D. Dressing, J.M. Jenkins, L.M. Walkowicz, N.M. Batalha, The false positive rate of Kepler and the occurrence of planets. Astrophys. J. 766, 81 (2013). doi:10.1088/0004-637X/766/2/81
B.J. Fulton, A. Shporer, J.N. Winn, M.J. Holman, A. Pál, J.Z. Gazak, Long-term transit timing monitoring and refined light curve parameters of HAT-P-13b. Astron. J. 142, 84 (2011). doi:10.1088/0004-6256/142/3/84
E. Gaidos, D.M. Williams, Seasonality on terrestrial extrasolar planets: inferring obliquity and surface conditions from infrared light curves. New Astron. 10, 67–77 (2004). doi:10.1016/j.newast.2004.04.009
E. Gaidos, D.A. Fischer, A.W. Mann, S. Lépine, On the nature of small planets around the coolest Kepler stars. Astrophys. J. 746, 36 (2012). doi:10.1088/0004-637X/746/1/36
R.L. Gilliland, W.J. Chaplin, E.W. Dunham, V.S. Argabright, W.J. Borucki, G. Basri, S.T. Bryson, D.L. Buzasi, D.A. Caldwell, Y.P. Elsworth, J.M. Jenkins, D.G. Koch, J. Kolodziejczak, A. Miglio, J. van Cleve, L.M. Walkowicz, W.F. Welsh, Kepler mission stellar and instrument noise properties. Astrophys. J. Suppl. Ser. 197, 6 (2011). doi:10.1088/0067-0049/197/1/6
B. Gladman, J. Coffey, Mercurian impact ejecta: meteorites and mantle. Meteorit. Planet. Sci. 44, 285–291 (2009). doi:10.1111/j.1945-5100.2009.tb00734.x
Y.-X. Gong, J.-L. Zhou, J.-W. Xie, X.-M. Wu, The effect of planet-planet scattering on the survival of exomoons. Astrophys. J. Lett. 769, 14 (2013). doi:10.1088/2041-8205/769/1/L14
O. Grasset, J. Schneider, C. Sotin, A study of the accuracy of mass-radius relationships for silicate-rich and ice-rich planets up to 100 Earth masses. Astrophys. J. 693, 722–733 (2009). doi:10.1088/0004-637X/693/1/722
S. Guilloteau, A. Dutrey, V. Piétu, Y. Boehler, A dual-frequency sub-arcsecond study of proto-planetary disks at mm wavelengths: first evidence for radial variations of the dust properties. Astron. Astrophys. 529, 105 (2011). doi:10.1051/0004-6361/201015209
N. Haghighipour, The formation and dynamics of super-Earth planets. Annu. Rev. Earth Planet. Sci. 41, 469–495 (2013). doi:10.1146/annurev-earth-042711-105340
B.M.S. Hansen, H.-Y. Shih, T. Currie, The pulsar planets: a test case of terrestrial planet assembly. Astrophys. J. 691, 382–393 (2009). doi:10.1088/0004-637X/691/1/382
A.P. Hatzes, The radial velocity detection of Earth-mass planets in the presence of activity noise: the case of α Centauri Bb. Astrophys. J. 770, 133 (2013). doi:10.1088/0004-637X/770/2/133
S.A. Hauck, J.-L. Margot, S.C. Solomon, R.J. Phillips, C.L. Johnson, F.G. Lemoine, E. Mazarico, T.J. McCoy, S. Padovan, S.J. Peale, M.E. Perry, D.E. Smith, M.T. Zuber, The curious case of Mercury’s internal structure. J. Geophys. Res. 118, 1204–1220 (2013). doi:10.1002/jgre.20091
C. Hayashi, 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, 35–53 (1981). doi:10.1143/PTPS.70.35
G. Hébrard, A. Lecavelier Des Étangs, A. Vidal-Madjar, J.-M. Désert, R. Ferlet, Evaporation rate of hot Jupiters and formation of Chthonian planets, in Extrasolar Planets: Today and Tomorrow, ed. by J. Beaulieu, A. Lecavelier Des Etangs, C. Terquem. Astronomical Society of the Pacific Conference Series, vol. 321, (2004), p. 203
T. Hirano, N. Narita, B. Sato, Y.H. Takahashi, K. Masuda, Y. Takeda, W. Aoki, M. Tamura, Y. Suto, Planet-planet eclipse and the Rossiter-McLaughlin effect of a multiple transiting system: joint analysis of the Subaru spectroscopy and the Kepler photometry. Astrophys. J. Lett. 759, 36 (2012). doi:10.1088/2041-8205/759/2/L36
M.J. Holman, N.W. Murray, The use of transit timing to detect terrestrial-mass extrasolar planets. Science 307, 1288–1291 (2005). doi:10.1126/science.1107822
A.W. Howard, G.W. Marcy, J.A. Johnson, D.A. Fischer, J.T. Wright, H. Isaacson, J.A. Valenti, J. Anderson, D.N.C. Lin, S. Ida, The occurrence and mass distribution of close-in super-Earths, Neptunes, and Jupiters. Science 330, 653 (2010). doi:10.1126/science.1194854
A.W. Howard, G.W. Marcy, S.T. Bryson, J.M. Jenkins, J.F. Rowe, N.M. Batalha, W.J. Borucki, D.G. Koch, E.W. Dunham, T.N. Gautier III, J. Van Cleve, W.D. Cochran, D.W. Latham, J.J. Lissauer, G. Torres, T.M. Brown, R.L. Gilliland, L.A. Buchhave, D.A. Caldwell, J. Christensen-Dalsgaard, D. Ciardi, F. Fressin, M.R. Haas, S.B. Howell, H. Kjeldsen, S. Seager, L. Rogers, D.D. Sasselov, J.H. Steffen, G.S. Basri, D. Charbonneau, J. Christiansen, B. Clarke, A. Dupree, D.C. Fabrycky, D.A. Fischer, E.B. Ford, J.J. Fortney, J. Tarter, F.R. Girouard, M.J. Holman, J.A. Johnson, T.C. Klaus, P. Machalek, A.V. Moorhead, R.C. Morehead, D. Ragozzine, P. Tenenbaum, J.D. Twicken, S.N. Quinn, H. Isaacson, A. Shporer, P.W. Lucas, L.M. Walkowicz, W.F. Welsh, A. Boss, E. Devore, A. Gould, J.C. Smith, R.L. Morris, A. Prsa, T.D. Morton, M. Still, S.E. Thompson, F. Mullally, M. Endl, P.J. MacQueen, Planet occurrence within 0.25 AU of solar-type stars from Kepler. Astrophys. J. Suppl. Ser. 201, 15 (2012). doi:10.1088/0067-0049/201/2/15
S. Ida, D.N.C. Lin, Toward a deterministic model of planetary formation. VI. Dynamical interaction and coagulation of multiple rocky embryos and super-Earth systems around solar-type stars. Astrophys. J. Lett. 719, 810–830 (2010). doi:10.1088/0004-637X/719/1/810
A. Isella, J.M. Carpenter, A.I. Sargent, Structure and evolution of pre-main-sequence circumstellar disks. Astrophys. J. Lett. 701, 260–282 (2009). doi:10.1088/0004-637X/701/1/260
J.M. Jenkins, D.A. Caldwell, H. Chandrasekaran, J.D. Twicken, S.T. Bryson, E.V. Quintana, B.D. Clarke, J. Li, C. Allen, P. Tenenbaum, H. Wu, T.C. Klaus, C.K. Middour, M.T. Cote, S. McCauliff, F.R. Girouard, J.P. Gunter, B. Wohler, J. Sommers, J.R. Hall, A.K. Uddin, M.S. Wu, P.A. Bhavsar, J. Van Cleve, D.L. Pletcher, J.A. Dotson, M.R. Haas, R.L. Gilliland, D.G. Koch, W.J. Borucki, Overview of the Kepler science processing pipeline. Astrophys. J. Lett. 713, 87–91 (2010). doi:10.1088/2041-8205/713/2/L87
R.E. Johnson, Thermally driven atmospheric escape. Astrophys. J. Lett. 716, 1573–1578 (2010). doi:10.1088/0004-637X/716/2/1573
E. Kambe, H. Ando, B. Sato, H. Izumiura, T. Sekii, D.B. Paulson, K. Yanagisawa, S. Masuda, H. Shibahashi, A.P. Hatzes, M. Martic, J.-C. Lebrun, D.E. Mkrtichian, L.L. Kiss, H. Bruntt, S.J. O’Toole, T.R. Bedding, Development of iodine cells for Subaru HDS and Okayama HIDES. III. An improvement on the radial-velocity measurement technique. Publ. Astron. Soc. Jpn. 60, 45 (2008)
G.M. Kennedy, S.J. Kenyon, Planet formation around stars of various masses: hot super-Earths. Astrophys. J. 682, 1264–1276 (2008). doi:10.1086/589436
S.J. Kenyon, B.C. Bromley, Terrestrial planet formation. I. The transition from oligarchic growth to chaotic growth. Astron. J. 131, 1837–1850 (2006). doi:10.1086/499807
D.M. Kipping, S.J. Fossey, G. Campanella, On the detectability of habitable exomoons with Kepler-class photometry. Mon. Not. R. Astron. Soc. 400, 398–405 (2009). doi:10.1111/j.1365-2966.2009.15472.x
D.M. Kipping, J. Hartman, L.A. Buchhave, A.R. Schmitt, G.Á. Bakos, D. Nesvorný, The hunt for exomoons with Kepler (HEK). II. Analysis of seven viable satellite-hosting planet candidates. Astrophys. J. 770, 101 (2013). doi:10.1088/0004-637X/770/2/101
D.G. Koch, W.J. Borucki, G. Basri, N.M. Batalha, T.M. Brown, D. Caldwell, J. Christensen-Dalsgaard, W.D. Cochran, E. DeVore, E.W. Dunham, T.N. Gautier III, J.C. Geary, R.L. Gilliland, A. Gould, J. Jenkins, Y. Kondo, D.W. Latham, J.J. Lissauer, G. Marcy, D. Monet, D. Sasselov, A. Boss, D. Brownlee, J. Caldwell, A.K. Dupree, S.B. Howell, H. Kjeldsen, S. Meibom, D. Morrison, T. Owen, H. Reitsema, J. Tarter, S.T. Bryson, J.L. Dotson, P. Gazis, M.R. Haas, J. Kolodziejczak, J.F. Rowe, J.E. Van Cleve, C. Allen, H. Chandrasekaran, B.D. Clarke, J. Li, E.V. Quintana, P. Tenenbaum, J.D. Twicken, H. Wu, Kepler mission design, realized photometric performance, and early science. Astrophys. J. Lett. 713, 79–86 (2010). doi:10.1088/2041-8205/713/2/L79
E. Kokubo, S. Ida, Oligarchic growth of protoplanets. Icarus 131, 171–178 (1998). doi:10.1006/icar.1997.5840
E. Kokubo, S. Ida, Formation of protoplanets from planetesimals in the solar nebula. Icarus 143, 15–27 (2000). doi:10.1006/icar.1999.6237
E. Kokubo, J. Kominami, S. Ida, Formation of terrestrial planets from protoplanets. I. Statistics of basic dynamical properties. Astrophys. J. 642, 1131–1139 (2006). doi:10.1086/501448
D. Kubas, J.P. Beaulieu, D.P. Bennett, A. Cassan, A. Cole, J. Lunine, J.B. Marquette, S. Dong, A. Gould, T. Sumi, V. Batista, P. Fouqué, S. Brillant, S. Dieters, C. Coutures, J. Greenhill, I. Bond, T. Nagayama, A. Udalski, E. Pompei, D.E.A. Nürnberger, J.B. Le Bouquin, A frozen super-Earth orbiting a star at the bottom of the main sequence. Astron. Astrophys. 540, 78 (2012). doi:10.1051/0004-6361/201015832
M.J. Kuchner, Volatile-rich Earth-mass planets in the habitable zone. Astrophys. J. 596, 105–108 (2003). doi:10.1086/378397
A. Léger, F. Selsis, C. Sotin, T. Guillot, D. Despois, D. Mawet, M. Ollivier, A. Labèque, C. Valette, F. Brachet, B. Chazelas, H. Lammer, A new family of planets? “Ocean-planets”. Icarus 169, 499–504 (2004). doi:10.1016/j.icarus.2004.01.001
A. Léger, O. Grasset, B. Fegley, F. Codron, A.F. Albarede, P. Barge, R. Barnes, P. Cance, S. Carpy, F. Catalano, C. Cavarroc, O. Demangeon, S. Ferraz-Mello, P. Gabor, J.-M. Grießmeier, J. Leibacher, G. Libourel, A.-S. Maurin, S.N. Raymond, D. Rouan, B. Samuel, L. Schaefer, J. Schneider, P.A. Schuller, F. Selsis, C. Sotin, The extreme physical properties of the CoRoT-7b super-Earth. Icarus 213, 1–11 (2011). doi:10.1016/j.icarus.2011.02.004
J.S. Lewis, Metal/silicate fractionation in the solar system. Earth Planet. Sci. Lett. 15, 286–290 (1972). doi:10.1016/0012-821X(72)90174-4
N.K. Lewis, A.P. Showman, J.J. Fortney, M.S. Marley, R.S. Freedman, K. Lodders, Atmospheric circulation of eccentric hot Neptune GJ436b. Astrophys. J. 720, 344–356 (2010). doi:10.1088/0004-637X/720/1/344
C.-H. Li, A.G. Glenday, D.F. Phillips, G. Furesz, N. Langellier, M. Webber, A. Zibrov, A.J. Benedick, G. Chang, L.-J. Chen, D. Sasselov, F. Kärtner, A. Szentgyorgyi, R.L. Walsworth, Green astro-comb for HARPS-N, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 8446 (2012). doi:10.1117/12.925799
D.N.C. Lin, P. Bodenheimer, D.C. Richardson, Orbital migration of the planetary companion of 51 Pegasi to its present location. Nature 380, 606–607 (1996). doi:10.1038/380606a0
J.J. Lissauer, D. Ragozzine, D.C. Fabrycky, J.H. Steffen, E.B. Ford, J.M. Jenkins, A. Shporer, M.J. Holman, J.F. Rowe, E.V. Quintana, N.M. Batalha, W.J. Borucki, S.T. Bryson, D.A. Caldwell, J.A. Carter, D. Ciardi, E.W. Dunham, J.J. Fortney, T.N. Gautier III, S.B. Howell, D.G. Koch, D.W. Latham, G.W. Marcy, R.C. Morehead, D. Sasselov, Architecture and dynamics of Kepler’s candidate multiple transiting planet systems. Astrophys. J. Suppl. Ser. 197, 8 (2011). doi:10.1088/0067-0049/197/1/8
C. Lovis, M. Mayor, F. Pepe, Y. Alibert, W. Benz, F. Bouchy, A.C.M. Correia, J. Laskar, C. Mordasini, D. Queloz, N.C. Santos, S. Udry, J.-L. Bertaux, J.-P. Sivan, An extrasolar planetary system with three Neptune-mass planets. Nature 441, 305–309 (2006). doi:10.1038/nature04828
G. Maciejewski, D. Dimitrov, M. Seeliger, S. Raetz, Ł. Bukowiecki, M. Kitze, R. Errmann, G. Nowak, A. Niedzielski, V. Popov, C. Marka, K. Goździewski, R. Neuhäuser, J. Ohlert, T.C. Hinse, J.W. Lee, C.-U. Lee, J.-N. Yoon, A. Berndt, H. Gilbert, C. Ginski, M.M. Hohle, M. Mugrauer, T. Röll, T.O.B. Schmidt, N. Tetzlaff, L. Mancini, J. Southworth, M. Dall’Ora, S. Ciceri, R. Zambelli, G. Corfini, H. Takahashi, K. Tachihara, J.M. Benkő, K. Sárneczky, G.M. Szabo, T.N. Varga, M. Vaňko, Y.C. Joshi, W.P. Chen, Multi-site campaign for transit timing variations of WASP-12 b: possible detection of a long-period signal of planetary origin. Astron. Astrophys. 551, 108 (2013). doi:10.1051/0004-6361/201220739
A.M. Mandell, S.N. Raymond, S. Sigurdsson, Formation of Earth-like planets during and after giant planet migration. Astrophys. J. 660, 823–844 (2007). doi:10.1086/512759
A.W. Mann, E. Gaidos, S. Lépine, E.J. Hilton, They might be giants: luminosity class, planet occurrence, and planet-metallicity relation of the coolest Kepler target stars. Astrophys. J. 753, 90 (2012). doi:10.1088/0004-637X/753/1/90
A.W. Mann, E. Gaidos, A. Kraus, E.J. Hilton, Testing the metal of late-type Kepler planet hosts with iron-clad methods. Astrophys. J. 770, 43 (2013). doi:10.1088/0004-637X/770/1/43
S. Mao, B. Paczynski, Gravitational microlensing by double stars and planetary systems. Astrophys. J. 374, 37–40 (1991). doi:10.1086/186066
M. Mayor, D. Queloz, A Jupiter-mass companion to a solar-type star. Nature 378, 355–359 (1995). doi:10.1038/378355a0
Y. Miguel, L. Kaltenegger, B. Fegley, L. Schaefer, Compositions of hot super-Earth atmospheres: exploring Kepler candidates. Astrophys. J. 742, 19 (2011). doi:10.1088/2041-8205/742/2/L19
M.C. Miller, D.P. Hamilton, Implications of the PSR 1257+12 planetary system for isolated millisecond pulsars. Astrophys. J. 550, 863–870 (2001). doi:10.1086/319813
J. Miralda-Escudé, Orbital perturbations of transiting planets: a possible method to measure stellar quadrupoles and to detect Earth-mass planets. Astrophys. J. 564, 1019–1023 (2002). doi:10.1086/324279
R. Montgomery, G. Laughlin, Formation and detection of Earth mass planets around low mass stars. Icarus 202, 1–11 (2009). doi:10.1016/j.icarus.2009.02.035
A. Morbidelli, J.I. Lunine, D.P. O’Brien, S.N. Raymond, K.J. Walsh, Building terrestrial planets. Annu. Rev. Earth Planet. Sci. 40, 251–275 (2012). doi:10.1146/annurev-earth-042711-105319
T.D. Morton, An efficient automated validation procedure for exoplanet transit candidates. Astrophys. J. 761, 6 (2012). doi:10.1088/0004-637X/761/1/6
P.S. Muirhead, K. Hamren, E. Schlawin, B. Rojas-Ayala, K.R. Covey, J.P. Lloyd, Characterizing the cool Kepler objects of interests. New effective temperatures, metallicities, masses, and radii of low-mass Kepler planet-candidate host stars. Astrophys. J. 750, 37 (2012a). doi:10.1088/2041-8205/750/2/L37
P.S. Muirhead, J.A. Johnson, K. Apps, J.A. Carter, T.D. Morton, D.C. Fabrycky, J.S. Pineda, M. Bottom, B. Rojas-Ayala, E. Schlawin, K. Hamren, K.R. Covey, J.R. Crepp, K.G. Stassun, J. Pepper, L. Hebb, E.N. Kirby, A.W. Howard, H.T. Isaacson, G.W. Marcy, D. Levitan, T. Diaz-Santos, L. Armus, J.P. Lloyd, Characterizing the cool KOIs. III. KOI 961: a small star with large proper motion and three small planets. Astrophys. J. 747, 144 (2012b). doi:10.1088/0004-637X/747/2/144
D.P. O’Brien, A. Morbidelli, H.F. Levison, Terrestrial planet formation with strong dynamical friction. Icarus 184, 39–58 (2006). doi:10.1016/j.icarus.2006.04.005
M. Ogihara, S. Ida, N-body simulations of satellite formation around giant planets: origin of orbital configuration of the Galilean moons. Astrophys. J. 753, 60 (2012)
A. Pál, Light-curve modelling for mutual transits. Mon. Not. R. Astron. Soc. 420, 1630–1635 (2012). doi:10.1111/j.1365-2966.2011.20151.x
L. Pasquini, S. Cristiani, R. García López, M. Haehnelt, M. Mayor, J. Liske, A. Manescau, G. Avila, H. Dekker, O. Iwert, B. Delabre, G. Lo Curto, V. D’Odorico, P. Molaro, M. Viel, E. Vanzella, P. Bonifacio, P. di Marcantonio, P. Santin, M. Comari, R. Cirami, I. Coretti, F.M. Zerbi, P. Spanò, M. Riva, R. Rebolo, G. Israelian, A. Herrero, M.R. Zapatero Osorio, F. Tenegi, B. Carswell, G. Becker, S. Udry, F. Pepe, C. Lovis, D. Naef, M. Dessauges, D. Mégevand, Codex, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 7735 (2010). doi:10.1117/12.856974
M.T. Penny, E. Kerins, N. Rattenbury, J.-P. Beaulieu, A.C. Robin, S. Mao, V. Batista, S. Calchi Novati, A. Cassan, P. Fouqué, I. McDonald, J.B. Marquette, P. Tisserand, M.R. Zapatero Osorio, ExELS: an exoplanet legacy science proposal for the ESA Euclid mission—I. Cold exoplanets. Mon. Not. R. Astron. Soc. 434, 2 (2013). doi:10.1093/mnras/stt927
F.A. Pepe, S. Cristiani, R. Rebolo Lopez, N.C. Santos, A. Amorim, G. Avila, W. Benz, P. Bonifacio, A. Cabral, P. Carvas, R. Cirami, J. Coelho, M. Comari, I. Coretti, V. de Caprio, H. Dekker, B. Delabre, P. di Marcantonio, V. D’Odorico, M. Fleury, R. García, J.M. Herreros Linares, I. Hughes, O. Iwert, J. Lima, J.-L. Lizon, G. Lo Curto, C. Lovis, A. Manescau, C. Martins, D. Mégevand, A. Moitinho, P. Molaro, M. Monteiro, M. Monteiro, L. Pasquini, C. Mordasini, D. Queloz, J.L. Rasilla, J.M. Rebordão, S. Santana Tschudi, P. Santin, D. Sosnowska, P. Spanò, F. Tenegi, S. Udry, E. Vanzella, M. Viel, M.R. Zapatero Osorio, F. Zerbi, ESPRESSO: the Echelle spectrograph for rocky exoplanets and stable spectroscopic observations, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 7735 (2010). doi:10.1117/12.857122
P.N. Peplowski, L.G. Evans, S.A. Hauck, T.J. McCoy, W.V. Boynton, J.J. Gillis-Davis, D.S. Ebel, J.O. Goldsten, D.K. Hamara, D.J. Lawrence, R.L. McNutt, L.R. Nittler, S.C. Solomon, E.A. Rhodes, A.L. Sprague, R.D. Starr, K.R. Stockstill-Cahill, Radioactive elements on Mercury’s surface from MESSENGER: implications for the planet’s formation and evolution. Science 333, 1850 (2011). doi:10.1126/science.1211576
E.A. Petigura, G.W. Marcy, A.W. Howard, A plateau in the planet population below twice the size of Earth. Astrophys. J. 770(1), 69 (2013)
J.A. Phillips, S.E. Thorsett, Planets around pulsars: a review. Astrophys. Space Sci. 212, 91–106 (1994). doi:10.1007/BF00984513
R. Pierrehumbert, E. Gaidos, Hydrogen greenhouse planets beyond the habitable zone. Astrophys. J. 734, 13 (2011). doi:10.1088/2041-8205/734/1/L13
F. Pont, R.L. Gilliland, C. Moutou, D. Charbonneau, F. Bouchy, T.M. Brown, M. Mayor, D. Queloz, N. Santos, S. Udry, Hubble space telescope time-series photometry of the planetary transit of HD 189733: no moon, no rings, starspots. Astron. Astrophys. 476, 1347–1355 (2007). doi:10.1051/0004-6361:20078269
S.B. Porter, W.M. Grundy, Post-capture evolution of potentially habitable exomoons. Astrophys. J. 736, 14 (2011). doi:10.1088/2041-8205/736/1/L14
D. Queloz, F. Bouchy, C. Moutou, A. Hatzes, G. Hébrard, R. Alonso, M. Auvergne, A. Baglin, M. Barbieri, P. Barge, W. Benz, P. Bordé, H.J. Deeg, M. Deleuil, R. Dvorak, A. Erikson, S. Ferraz Mello, M. Fridlund, D. Gandolfi, M. Gillon, E. Guenther, T. Guillot, L. Jorda, M. Hartmann, H. Lammer, A. Léger, A. Llebaria, C. Lovis, P. Magain, M. Mayor, T. Mazeh, M. Ollivier, M. Pätzold, F. Pepe, H. Rauer, D. Rouan, J. Schneider, D. Segransan, S. Udry, G. Wuchterl, The CoRoT-7 planetary system: two orbiting super-Earths. Astron. Astrophys. 506, 303–319 (2009). doi:10.1051/0004-6361/200913096
M.V. Radovan, G.F. Cabak, L.H. Laiterman, C.T. Lockwood, S.S. Vogt, A radial velocity spectrometer for the automated planet finder telescope at lick observatory, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 7735 (2010). doi:10.1117/12.857726
D. Ragozzine, M.J. Holman, The value of systems with multiple transiting planets (2010). arXiv e-prints
S. Rappaport, A. Levine, E. Chiang, I. El Mellah, J. Jenkins, B. Kalomeni, E.S. Kite, M. Kotson, L. Nelson, L. Rousseau-Nepton, K. Tran, Possible disintegrating short-period super-Mercury orbiting KIC 12557548. Astrophys. J. 752, 1 (2012). doi:10.1088/0004-637X/752/1/1
S.N. Raymond, A.M. Mandell, S. Sigurdsson, Exotic Earths: forming habitable worlds with giant planet migration. Science 313, 1413–1416 (2006). doi:10.1126/science.1130461
S.N. Raymond, J. Scalo, V.S. Meadows, A decreased probability of habitable planet formation around low-mass stars. Astrophys. J. 669, 606–614 (2007). doi:10.1086/521587
S.N. Raymond, R. Barnes, A.M. Mandell, Observable consequences of planet formation models in systems with close-in terrestrial planets. Mon. Not. R. Astron. Soc. 384, 663–674 (2008). doi:10.1111/j.1365-2966.2007.12712.x
S.N. Raymond, D.P. O’Brien, A. Morbidelli, N.A. Kaib, Building the terrestrial planets: constrained accretion in the inner solar system. Icarus 203, 644–662 (2009). doi:10.1016/j.icarus.2009.05.016
A. Reiners, J.L. Bean, K.F. Huber, S. Dreizler, A. Seifahrt, S. Czesla, Detecting planets around very low mass stars with the radial velocity method. Astrophys. J. 710, 432–443 (2010). doi:10.1088/0004-637X/710/1/432
I. Ribas, E.F. Guinan, M. Güdel, M. Audard, Evolution of the solar activity over time and effects on planetary atmospheres. I. High-energy irradiances (1–1700 Å). Astrophys. J. 622, 680–694 (2005). doi:10.1086/427977
E.J. Rivera, J.J. Lissauer, R.P. Butler, G.W. Marcy, S.S. Vogt, D.A. Fischer, T.M. Brown, G. Laughlin, G.W. Henry, A ∼7.5 M⊕ planet orbiting the nearby star, GJ 876. Astrophys. J. 634, 625–640 (2005). doi:10.1086/491669
L.A. Rogers, S. Seager, A framework for quantifying the degeneracies of exoplanet interior compositions. Astrophys. J. 712, 974–991 (2010). doi:10.1088/0004-637X/712/2/974
G. Rupprecht, F. Pepe, M. Mayor, D. Queloz, F. Bouchy, G. Avila, W. Benz, J.-L. Bertaux, X. Bonfils, T. Dall, B. Delabre, H. Dekker, W. Eckert, M. Fleury, A. Gilliotte, D. Gojak, J.C. Guzman, D. Kohler, J.-L. Lizon, G. Lo Curto, A. Longinotti, C. Lovis, D. Megevand, L. Pasquini, J. Reyes, J.-P. Sivan, D. Sosnowska, R. Soto, S. Udry, A. Van Kesteren, L. Weber, U. Weilenmann, The exoplanet hunter HARPS: performance and first results, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, ed. by A.F.M. Moorwood, M. Iye, vol. 5492 (2004), pp. 148–159. doi:10.1117/12.551267
R. Sanchis-Ojeda, D.C. Fabrycky, J.N. Winn, T. Barclay, B.D. Clarke, E.B. Ford, J.J. Fortney, J.C. Geary, M.J. Holman, A.W. Howard, J.M. Jenkins, D. Koch, J.J. Lissauer, G.W. Marcy, F. Mullally, D. Ragozzine, S.E. Seader, M. Still, S.E. Thompson, Alignment of the stellar spin with the orbits of a three-planet system. Nature 487, 449–453 (2012). doi:10.1038/nature11301
J. Sanz-Forcada, G. Micela, I. Ribas, A.M.T. Pollock, C. Eiroa, A. Velasco, E. Solano, D. García-Álvarez, Estimation of the XUV radiation onto close planets and their evaporation. Astron. Astrophys. 532, 6 (2011). doi:10.1051/0004-6361/201116594
T. Sasaki, G.R. Stewart, S. Ida, Origin of the different architectures of the Jovian and Saturnian satellite systems. Astrophys. J. 714, 1052–1064 (2010). doi:10.1088/0004-637X/714/2/1052
J. Schneider, C. Dedieu, P. Le Sidaner, R. Savalle, I. Zolotukhin, Defining and cataloging exoplanets: the exoplanet.eu database. Astron. Astrophys. 532, 79 (2011). doi:10.1051/0004-6361/201116713
C. Schwab, J.F.P. Spronck, A. Tokovinin, A. Szymkowiak, M. Giguere, D.A. Fischer, Performance of the CHIRON high-resolution Echelle spectrograph, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 8446 (2012). doi:10.1117/12.925108
S. Seager, M. Kuchner, C.A. Hier-Majumder, B. Militzer, Mass-radius relationships for solid exoplanets. Astrophys. J. 669, 1279–1297 (2007). doi:10.1086/521346
S. Sigurdsson, Genesis of a planet in Messier 4. Astrophys. J. 415, 43–46 (1993). doi:10.1086/187028
F. Sohl, G. Schubert, T. Spohn, Geophysical constraints on the composition and structure of the Martian interior. J. Geophys. Res. 110, 12008 (2005). doi:10.1029/2005JE002520
J.F.P. Spronck, D.A. Fischer, Z.A. Kaplan, C. Schwab, Fiber scrambling for precise radial velocities at Lick and Keck observatories, in Society of Photo-Optical Instrumentation Engineers (SPIE) Conference Series, vol. 8446 (2012). doi:10.1117/12.926289
T. Steinmetz, T. Wilken, C. Araujo-Hauck, R. Holzwarth, T.W. Hänsch, L. Pasquini, A. Manescau, S. D’Odorico, M.T. Murphy, T. Kentischer, W. Schmidt, T. Udem, Laser frequency combs for astronomical observations. Science 321, 1335 (2008). doi:10.1126/science.1161030
K.B. Stevenson, J. Harrington, N.B. Lust, N.K. Lewis, G. Montagnier, J.I. Moses, C. Visscher, J. Blecic, R.A. Hardy, P. Cubillos, C.J. Campo, Two nearby sub-Earth-sized exoplanet candidates in the GJ 436 system. Astrophys. J. 755, 9 (2012). doi:10.1088/0004-637X/755/1/9
P. Tenenbaum, J.L. Christiansen, J.M. Jenkins, J.F. Rowe, S. Seader, D.A. Caldwell, B.D. Clarke, J. Li, E.V. Quintana, J.C. Smith, M.C. Stumpe, S.E. Thompson, J.D. Twicken, J. Van Cleve, W.J. Borucki, M.T. Cote, M.R. Haas, D.T. Sanderfer, F.R. Girouard, T.C. Klaus, C.K. Middour, B. Wohler, N.M. Batalha, T. Barclay, J.E. Nickerson, Detection of potential transit signals in the first three quarters of Kepler mission data. Astrophys. J. Suppl. Ser. 199, 24 (2012). doi:10.1088/0067-0049/199/1/24
C. Terquem, J.C.B. Papaloizou, Migration and the formation of systems of hot super-Earths and Neptunes. Astrophys. J. 654, 1110–1120 (2007). doi:10.1086/509497
F. Tian, Thermal escape from super Earth atmospheres in the habitable zones of M stars. Astrophys. J. 703, 905–909 (2009). doi:10.1088/0004-637X/703/1/905
G. Torres, J. Andersen, A. Giménez, Accurate masses and radii of normal stars: modern results and applications. Astron. Astrophys. Rev. 18, 67–126 (2010). doi:10.1007/s00159-009-0025-1
C. Tully, R.E. Johnson, Low energy collisions between ground-state oxygen atoms. Planet. Space Sci. 49, 533–537 (2001). doi:10.1016/S0032-0633(01)00002-2
D. Valencia, D.D. Sasselov, R.J. O’Connell, Detailed models of super-Earths: how well can we infer bulk properties? Astrophys. J. 665, 1413–1420 (2007). doi:10.1086/519554
D. Valencia, M. Ikoma, T. Guillot, N. Nettelmann, Composition and fate of short-period super-Earths. The case of CoRoT-7b. Astron. Astrophys. 516, 20 (2010). doi:10.1051/0004-6361/200912839
J.A. Valenti, R.P. Butler, G.W. Marcy, Determining spectrometer instrumental profiles using FTS reference spectra. Publ. Astron. Soc. Pac. 107, 966 (1995). doi:10.1086/133645
L.M. van Haaften, G. Nelemans, R. Voss, P.G. Jonker, Formation of the planet around the millisecond pulsar J1719-1438. Astron. Astrophys. 541, 22 (2012). doi:10.1051/0004-6361/201218798
K.J. Walsh, A. Morbidelli, S.N. Raymond, D.P. O’Brien, A.M. Mandell, A low mass for Mars from Jupiter’s early gas-driven migration. Nature 475, 206–209 (2011). doi:10.1038/nature10201
W.R. Ward, Protoplanet migration by nebula tides. Icarus 126, 261–281 (1997). doi:10.1006/icar.1996.5647
S.J. Weidenschilling, Aerodynamics of solid bodies in the solar nebula. Mon. Not. R. Astron. Soc. 180, 57–70 (1977a)
S.J. Weidenschilling, The distribution of mass in the planetary system and solar nebula. Astrophys. Space Sci. 51, 153–158 (1977b). doi:10.1007/BF00642464
S.J. Weidenschilling, Iron/silicate fractionation and the origin of Mercury. Icarus 35, 99–111 (1978). doi:10.1016/0019-1035(78)90064-7
R. Weidling, C. Güttler, J. Blum, Free collisions in a microgravity many-particle experiment. I. Dust aggregate sticking at low velocities. Icarus 218, 688–700 (2012). doi:10.1016/j.icarus.2011.10.002
J.P. Williams, L.A. Cieza, Protoplanetary disks and their evolution. Annu. Rev. Astron. Astrophys. 49, 67–117 (2011). doi:10.1146/annurev-astro-081710-102548
A. Wolszczan, Confirmation of Earth-mass planets orbiting the millisecond pulsar PSR B1257+12. Science 264, 538–542 (1994). doi:10.1126/science.264.5158.538
A. Wolszczan, Discovery of pulsar planets. New Astron. Rev. 56, 2–8 (2012). doi:10.1016/j.newar.2011.06.002
J.T. Wright, B.S. Gaudi, Exoplanet detection methods, in Planets, Stars and Stellar Systems, ed. by T.D. Oswalt, L.M. French, P. Kalas (Springer, Berlin, 2013), p. 489. doi:10.1007/978-94-007-5606-9_10. ISBN 978-94-007-5605-2
J.T. Wright, S. Upadhyay, G.W. Marcy, D.A. Fischer, E.B. Ford, J.A. Johnson, Ten new and updated multiplanet systems and a survey of exoplanetary systems. Astrophys. J. 693, 1084–1099 (2009). doi:10.1088/0004-637X/693/2/1084
A.N. Youdin, S.J. Kenyon, in From Disks to Planets, ed. by T.D. Oswalt, L.M. French, P. Kalas (2013), p. 1. doi:10.1007/978-94-007-5606-9-1
J. Zendejas, A. Segura, A.C. Raga, Atmospheric mass loss by stellar wind from planets around main sequence M stars. Icarus 210, 539–544 (2010). doi:10.1016/j.icarus.2010.07.013
J.-L. Zhou, S.J. Aarseth, D.N.C. Lin, M. Nagasawa, Origin and ubiquity of short-period Earth-like planets: evidence for the sequential accretion theory of planet formation. Astrophys. J. 631, 85–88 (2005). doi:10.1086/497094
A. Zsom, C.W. Ormel, C. Güttler, J. Blum, C.P. Dullemond, The outcome of protoplanetary dust growth: pebbles, boulders, or planetesimals? II. Introducing the bouncing barrier. Astron. Astrophys. 513, 57 (2010). doi:10.1051/0004-6361/200912976
Acknowledgements
This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with the National Aeronautics and Space Administration under the Exoplanet Exploration Program. Some of the data presented in this paper were obtained from the Mikulski Archive for Space Telescopes (MAST). STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS5-26555. Support for MAST for non-HST data is provided by the NASA Office of Space Science via grant NNX09AF08G and by other grants and contracts. This paper includes data collected by the Kepler mission. Funding for the Kepler mission is provided by the NASA Science Mission directorate. EG acknowledges support from NASA grants NNX10AI90G and NNX11AC33G. We thank Y. Kokubo for providing Fig. 5, E. Kite for commenting on an earlier version of this manuscript and E. Petigura and A. Howard for helpful discussions.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Sinukoff, E., Fulton, B., Scuderi, L. et al. Below One Earth: The Detection, Formation, and Properties of Subterrestrial Worlds. Space Sci Rev 180, 71–99 (2013). https://doi.org/10.1007/s11214-013-0019-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11214-013-0019-1