Nuestra Galaxia está repleta de planetas como la Tierra.
Como en los estudios anteriores, en esta ocasión los investigadores examinaron 226 candidatos planetarios procedentes de 152 sistemas solares diferentes procedentes del recuento y catalogación realizado por la misión Kepler. Mas de 3/4 de esos planetas candidatos son menores que Neptuno, (4 veces el diámetro de la Tierra) y algunos de ellos son incluso de tamaño similar a la Tierra.
Los astrónomos estudian la formación de estos planetas en el espectro estelar, pues debido al disco protoplanetario, cuando el nivel de elementos pesados es elevado, la tendencia es propicia a la formación de los planetas rocosos, tal y como expone Buchhave. En cambio, cuando la composición es elevada en metales, la tendencia es a la formación de Planetas del Tipo Júpiter. Por tanto dependiendo de la estrella, pueden darse o no las condiciones para la formación de los planetas Terrestres. Los resultados de la misión Kepler tras analizar 226 candidatos de 150 sistemas solares diferentes, podemos aseverar que los planetas terrestres se forman incluso en estrellas que tienen un contenido cuatro veces menor de metales que nuestro Sol, lo que haría de los planetas Terrestres la regla general en la formación de planetas en nuestra Galaxia y por tanto un auténtica incubadora de vida ahí fuera.
En palabras del propio Buchhave, la hipótesis de vida extraterrestre más allá de nuestro sistema Solar, está cada vez más reforzada a la luz de los nuevos hallazgos estudiados, ya que al menos 3/4 partes de os Sistemas Solares analizados, podrían albergar planetas Terrestres con tamaños que oscilan entre el de la Tierra hasta aquellos ligeramente inferiores a Neptuno.
Las zonas de habitabilidad también encajan con la formación de dichos planetas, lo que nos sugiere un amplio espectro de posibilidades y lugares donde buscar, una vez que ya sabemos que la formación de los planetas terrestres se produce preferentemente en entornos estelares incluso cuatro veces más pobres en metales que el nuestro.
Respecto al tiempo necesario para la formación de planetas Terrestres, se requeriría un mínimo de unos 2.000 a 3000 millones de años desde el nacimiento de las estrellas anfitrionas, lo que encaja bastante bien con los estudios que hasta ahora conocemos respecto de nuestro Sistema Solar.
La lista no es “numerus clausus”. Hablamos de listas abiertas en las que cada vez aparecerán nuevos datos que nos permitirán indagar nuevas conclusiones, respecto a la formación, composición y antigüedad de estos planetas y la composición de sus soles, etc…
Recordemos que hace apenas dos años, a la luz de los primeros datos de la misión Kepler , el Dr. Sasselov ya abrió la veda al afirmar en una polémica rueda de prensa que nuestra Galaxi estaba llena de Planetas capaces de albergar vida.
El estudio de Lars A. Buchhave y su equipo, viene a confirmar empíricamente y a ampliar con datos mucho más precisos que los aportados entonces por Sasselov, sus afirmaciones.
Seguidamente reproducimos un diagrama de algunos de los datos de la misión Kepler, indicativos de lo que ya Sasselov expusiera en agosto de 2010.
Especial mención merecen los Planetas denominados Kepler-20 correspondiente a un Sistema con tres Planetas rocosos.
El mayor de los tres tiene 1.43 veces el radio de la Tierra y 2.9 veces su volumen. Los otros dos, respectivamente tienen 1.03 y 0.87 veces e radio de la Tierra. Kepler 20 es un sistema binario de estrellas. De ellos el último Kepler F, parece contener una composición rica en elementos metálicos y vapor de Agua.
Ver Detalle del estudio sobre Kepler 20:
Since the discovery of the first extrasolar giant planets around Sun-like stars, evolving observational capabilities have brought us closer to the detection of true Earth analogues. The size of an exoplanet can be determined when it periodically passes in front of (transits) its parent star, causing a decrease in starlight proportional to its radius. The smallest exoplanet hitherto discovered has a radius 1.42 times that of the Earth’s radius (R_⊕ plus), and hence has 2.9 times its volume. Here we report the discovery of two planets, one Earth-sized (1.03R_⊕) and the other smaller than the Earth (0.87R_⊕), orbiting the star Kepler-20, which is already known to host three other, larger, transiting planets. The gravitational pull of the new planets on the parent star is too small to measure with current instrumentation. We apply a statistical method to show that the likelihood of the planetary interpretation of the transit signals is more than three orders of magnitude larger than that of the alternative hypothesis that the signals result from an eclipsing binary star. Theoretical considerations imply that these planets are rocky, with a composition of iron and silicate. The outer planet could have developed a thick water vapour atmosphere.Dada la ingente documentación sobre la materia, recomendamos la lectura de las siguientes referencias bibliográficas detalladas:
I.-Referencias a los hallazgos de la misión Kepler y análisis de los sistemas exoplanetarios.
| 1. | TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION OF TWO MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION ANALYSIS (…) Jason H. Steffen / Joshua A. Carter / Francois Fressin (…) Borucki / Stephen T. Bryson / Lars A. Buchhave / Christopher J. Burke / Douglas A. Caldwell / (…) / the Kepler Science Team , The Astrophysical Journal, 750 (2), p.113, May 2012 doi:10.1088/0004-637X/750/2/113 …Printed in the U.S.A. TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION…MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION…Stephen T. Bryson5 , Lars A. Buchhave10,11…Bill Wohler8 , and the Kepler Science Team 1 Astronomy… |
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KEPLER-14b: A MASSIVE HOT JUPITER TRANSITING AN F STAR IN A CLOSE VISUAL BINARY Lars A. Buchhave / David W. Latham / Joshua A. Carter / Jean-Michel Désert / Guillermo Torres / Elisabeth (…) David R. Ciardi / Craig Kulesa / (…) / Ronald (…) , The Astrophysical Journal Supplement Series, 197 (1), p.3, Nov 2011 doi:10.1088/0067-0049/197/1/3 …AN F STAR IN A CLOSE VISUAL BINARY Lars A. Buchhave1…parameters. Kepler-14b (KOI-98…2011 November Buchhave et al. 0.998 0.999 1…2011 November Buchhave et al. Figure…optics images of Kepler-14, showing a 2 × 2 field of… |
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Kepler-22b: A 2.4 EARTH-RADIUS PLANET IN THE HABITABLE ZONE OF A SUN-LIKE STAR (…) Fressin / Guillermo Torres / Douglas A. Caldwell / Jørgen Christensen-Dalsgaard (…) Still / Jill Tarter / Sarah Ballard / Lars A.Buchhave / (…) / Mia (…) , The Astrophysical Journal, 745 (2), p.120, Feb 2012 doi:10.1088/0004-637X/745/2/120 …reserved. Printed in the U.S.A. Kepler-22b: A 2.4 EARTH-RADIUS PLANET IN THE…Jill Tarter3 , Sarah Ballard4 , Lars A. Buchhave19,20 , Josh Carter21…time-series photometry from NASA’s Kepler spacecraft reveals a transiting… |
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KEPLER-18b, c, AND d: A SYSTEM OF THREE PLANETS CONFIRMED BY TRANSIT TIMING VARIATIONS, LIGHT CURVE VALIDATION, WARM-SPITZER … (…) Stephen T. Bryson / Joshua A. Carter / David R. Ciardi (…) Knutson / K. Kinemuchi / John A. Johnson / Jon M. Jenkins (…) III / Eric B. Ford / (…) / Natalie (…) , The Astrophysical Journal Supplement Series, 197 (1), p.7, Nov 2011 doi:10.1088/0067-0049/197/1/7 …Printed in the U.S.A. KEPLER-18b, c, AND d: A SYSTEM OF THREE PLANETS…Douglas Caldwell4,11 , Lars Buchhave23,24 , Timothy…nasa.gov, Douglas.A.Caldwell@nasa.gov…star, which we designate Kepler-18. The transit signals… |
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KEPLER-20: A SUN-LIKE STAR WITH THREE SUB-NEPTUNE EXOPLANETS AND TWO EARTH-SIZE CANDIDATES (…) Guillermo Torres / Francois Fressin / Leslie A. Rogers / Jean-Michel Désert / Lars A. Buchhave / David W. Latham / Samuel N. Quinn / (…) / Elliott P. Horch (…) , The Astrophysical Journal, 749 (1), p.15, Apr 2012 doi:10.1088/0004-637X/749/1/15 …reserved. Printed in the U.S.A. KEPLER-20: A SUN-LIKE STAR WITH THREE SUB-NEPTUNE…Rogers5 , Jean-Michel D´esert2 , Lars A. Buchhave6,7 , David W. Latham2…ABSTRACT We present the discovery of the Kepler-20 planetary system, which we… |
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KEPLER-21b: A 1.6 R Earth PLANET TRANSITING THE BRIGHT OSCILLATING F SUBGIANT STAR HD 179070Based in part on observations … (…) Christensen-Dalsgaard / Yvonne Elsworth / Rafael A. García / Günter Houdek / Christoffer (…) Molenda-Żakowicz / Michael J. Thompson / Graham A. Verner / (…) / Mark Everett (…) , The Astrophysical Journal, 746 (2), p.123, Feb 2012 doi:10.1088/0004-637X/746/2/123 …reserved. Printed in the U.S.A. KEPLER-21b: A 1.6 REarth PLANET TRANSITING THE…Lissauer2 , David W. Latham4 , Lars A. Buchhave22,35 , Thomas N. Gautier…2012 January 31 ABSTRACT We present Kepler observations of the bright (V… |
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A closely packed system of low-mass, low-density planets transiting Kepler-11 : Nature : Nature Publishing Group [120K] Feb 2011 …Next abstract A closely packed…transiting Kepler-11 Jack J…Marcy 5 Jerome A. Orosz 6 Jason…Bryson 1 Lars A. Buchhave 9 DouglasA…Kepler-11b and Kepler-11c may have…Torres, Joshua A. Carter…Copenhagen, Denmark Lars A. Buchhave McDonald Observatory… |
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KEPLER-15b: A HOT JUPITER ENRICHED IN HEAVY ELEMENTS AND THE FIRST KEPLER MISSION PLANET CONFIRMED WITH THE HOBBY-EBERLY … Michael Endl / Phillip J. MacQueen / William D. Cochran / Erik J. Brugamyer / Lars A. Buchhave / Jason Rowe / Phillip Lucas / (…) / William (…) , The Astrophysical Journal Supplement Series, 197 (1), p.13, Nov 2011 doi:10.1088/0067-0049/197/1/13 …reserved. Printed in the U.S.A. KEPLER-15b: A HOT JUPITER ENRICHED IN HEAVY ELEMENTS AND THE FIRST KEPLER MISSION PLANET CONFIRMED WITH THE HOBBY…Cochran1 , Erik J. Brugamyer2 , Lars A. Buchhave3 , Jason Rowe4 , Phillip… |
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Kepler-16: a transiting circumbinary planet. (…) Doyle, Laurance R / Carter, Joshua A / Fabrycky, Daniel C / Slawson, Robert (…) Winn, Joshua N / Orosz, Jerome A / Prša, Andrej / Welsh, William F (…) Latham, David / (…) / Fortney, Jonathan (…) , Science (New York, N.Y.), 333 (6049), p.1602-1606, Sep 2011 We report the detection of a planet whose orbit surrounds a pair of low-mass stars. Data from the Kepler spacecraft reveal transits of the planet across…comparable to Saturn in mass and size and is on a nearly circular 229-day orbit around its… |
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Star Lite: You Don’t Need Heavy Metals to Build a Good Planet
http://www.time.com/time/health/article/0,8599,2117179,00.html#ixzz1xxAF65dg
III.-Referencias adicionales sobre el hallazgo y Últimos estudios relevantes:
| 1. | Low metal stars may nurture Earthlike worlds Grossman, Lisa, New Scientist, 214 (2869), p.11, Jun 2012 doi:10.1016/S0262-4079(12)61527-9 …makes sense because a proto-planetary…planets. There was a problem, though…survey team led by Lars Buchhave of the University…identified by the Kepler Space Telescope , to…composition. Stars with a metal content as low… |
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ALMOST ALL OF KEPLER‘S MULTIPLE-PLANET CANDIDATES ARE PLANETS Jack J. Lissauer / Geoffrey W. Marcy / Jason F. Rowe / Stephen T. Bryson / Elisabeth Adams / Lars A. Buchhave / David R. Ciardi / (…) / Ronald L. Gilliland (…) , The Astrophysical Journal, 750 (2), p.112, May 2012 doi:10.1088/0004-637X/750/2/112 …reserved. Printed in the U.S.A. ALMOST ALL OF KEPLER’S MULTIPLE-PLANET CANDIDATES…Bryson1 , Elisabeth Adams4 , Lars A. Buchhave5,6 , David R. Ciardi7…that the overwhelming majority of Kepler candidate multiple transiting systems… |
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TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION OF TWO MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION ANALYSIS (…) Jason H. Steffen / Joshua A. Carter / Francois Fressin (…) Borucki / Stephen T. Bryson / Lars A. Buchhave / Christopher J. Burke / Douglas A. Caldwell / (…) / the Kepler Science Team , The Astrophysical Journal, 750 (2), p.113, May 2012 doi:10.1088/0004-637X/750/2/113 …Printed in the U.S.A. TRANSIT TIMING OBSERVATIONS FROM KEPLER. II. CONFIRMATION…MULTIPLANET SYSTEMS VIA A NON-PARAMETRIC CORRELATION…Stephen T. Bryson5 , Lars A. Buchhave10,11…Bill Wohler8 , and the Kepler Science Team 1 Astronomy… |
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TRANSIT TIMING OBSERVATIONS FROM KEPLER. IV. CONFIRMATION OF FOUR MULTIPLE-PLANET SYSTEMS BY SIMPLE PHYSICAL MODELS (…) B. Ford / Jason H. Steffen / Jason F. Rowe / Joshua A. Carter / Althea V. Moorhead / Natalie M. Batalha / William J. Borucki / (…) / William (…) , The Astrophysical Journal, 750 (2), p.114, May 2012 doi:10.1088/0004-637X/750/2/114 …Valenti & Fischer 2005), as well as a newly formulated analysis called SPC (L. A. Buchhave et al., in preparation), to obtain…and when possible v sin i. For Kepler-31 we did not obtain a spectrum, but instead adopted these… |
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Transit Timing Observations from Kepler. IV. Confirmation of Four Multiple-planet Systems by Simple Physical Models Fabrycky, Daniel C. / Ciardi, David R., article, May 2012 …Valenti & Fischer 2005), as well as a newly formulated analysis called SPC (L. A. Buchhave et al., in preparation), to obtain…and when possible v sin i. For Kepler-31 we did not obtain a spectrum, but instead adopted these… |
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Almost All of Kepler‘s Multiple-planet Candidates Are Planets Lissauer, Jack J. / Marcy, Geoffrey W. / Rowe, Jason F. / Bryson, Stephen T. / Adams, Elisabeth / Buchhave, Lars A. / Ciardi, David R. / (…) / Geary (…) , article, May 2012 …Logo CaltechAUTHORS A Caltech Library Service…Login Almost All of Kepler‘s Multiple-planet…and Adams, Elisabeth and Buchhave, Lars A. and Ciardi, David…2012) Almost All of Kepler‘s Multiple-planet… |
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QATAR-2: A K DWARF ORBITED BY A TRANSITING HOT JUPITER AND A MORE MASSIVE COMPANION IN AN OUTER ORBIT Marta L. Bryan / Khalid A. Alsubai / David W. Latham / Neil (…) Cameron / Samuel N. Quinn / Joshua A. Carter / Benjamin J. Fulton / (…) / Gilbert A. Esquerdo (…) , The Astrophysical Journal, 750 (1), p.84, May 2012 doi:10.1088/0004-637X/750/1/84 …Marta L. Bryan1 , Khalid A. Alsubai2 , David W. Latham3…Samuel N. Quinn3 , Joshua A. Carter3,12 , Benjamin…Berlind3 , Warren R. Brown3 ,Lars A. Buchhave6,7 , Michael…contrast to that found by Kepler for multi-transiting systems… |
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The Transiting Circumbinary Planets Kepler-34 and Kepler-35 Welsh, William F. / Orosz, Jerome A. / Carter, Joshua A. / Fabrycky, Daniel C. / Ford, Eric B. / Lissauer (…) Natalie / Bloemen, Steven / (…) / Caldwell, Douglas A (…) , article, Apr 2012 …additional transiting circumbinary planets, Kepler-34 and Kepler-35. Each is a low-density gas giant planet on an orbit…two Sun-like stars every 289 days, while Kepler-35 orbits a pair of smaller stars (89% and 81% of the… |
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