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Coordinates: Sky map 19h 10m 50s, +47° 19′ 59″
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| name = Kepler-14
| name = Kepler-14
}}
}}
{{Starbox character
{{Starbox observe
| constell = [[Lyra (constellation)|Lyra]]
| class = F<ref name=EPE />
| epoch = J2000
| ra = {{RA|19|10|50.110}}<ref name=UCAC3>{{cite journal|author1=Zacharias, N.|title=Third U.S. Naval Observatory CCD Astrograph Catalog (UCAC3)|journal=VizieR On-line Data Catalog|date=2009|bibcode=2009yCat.1315....0Z}}</ref>
| dec = {{DEC|+47|19|58.87}}<ref name=UCAC3/>
| appmag_v = 12.00<ref name=TYC2>{{cite journal|title=The Tycho-2 catalogue of the 2.5 million brightest stars|author1=Høg, E.|display-authors=etal|date=2000|journal=Astronomy and Astrophysics|volume=355|pages=L27–L30|bibcode=2000A&A...355L..27H}}</ref>
}}
}}
{{Starbox astrometry
{{Starbox astrometry
| dist_pc = 980<ref name=EPE />
|prop_mo_ra = 1.0<ref name=UCAC3/>
|prop_mo_dec = -10.2<ref name=UCAC3/>
|dist_ly = 3200
|dist_pc = 980<ref name=EPE />
}}
{{Starbox character
| class = F<ref name=EPE />
}}
}}
{{Starbox orbit
{{Starbox orbit
| primary = Kepler-14A
| primary = Kepler-14A
| name = Kepler-14B
| name = Kepler-14B
| period = ~2800<ref name=Buchhave2011 />
| period = ~2800<ref name="Buchhave2011"/>
| axis_unitless = 280 [[astronomical unit|AU]]<ref name=Buchhave2011 />
| axis_unitless = 280 [[astronomical unit|AU]]<ref name=Buchhave2011 />
}}
}}
{{Starbox detail
{{Starbox detail
| source = <!--[source url]-->
| source = <ref name="Buchhave2011"/>
| mass = 1.512 (± 0.043)<ref name=Buchhave2011 />
| mass = 1.512 (± 0.043)
| radius = 2.048 {{±|0.112|0.084}}<ref name=Buchhave2011 />
| radius = 2.048 {{±|0.112|0.084}}
| gravity =
| gravity = <!--Surface gravity (given as the base 10 logarithm expressed in cgs units)-->
| luminosity = 6.29 {{±|0.75|0.58}}<ref name=Buchhave2011 />
| luminosity = 6.29 {{±|0.75|0.58}}
| temperature = 6395 (± 60)<ref name=Buchhave2011 />
| temperature = 6395 (± 60)
| metal = +0.12 (± 0.06)<ref name=Buchhave2011 />
| metal = +0.12 (± 0.06)
| rotational_velocity = 7.9 (± 1.0)<ref name=Buchhave2011 />
| rotational_velocity = 7.9 (± 1.0)
| age_gyr = 2.2 {{±|0.2|0.1}}<ref name=Buchhave2011 />
| age_gyr = 2.2 {{±|0.2|0.1}}
}}
{{Starbox catalog
| names = [[Kepler object of interest|KOI]]-98, [[Kepler Input Catalog|KIC]] 10264660, [[Tycho-2 Catalogue|TYC]] 3546-413-1, [[Guide Star Catalog|GSC]] 03546-00413, [[Washington Double Star Catalog|WDS]] J19108+4720AB, [[2MASS]] J19105011+4719589
}}
{{Starbox reference
|Simbad=KOI-98
|KIC=10264660
}}
}}
{{Starbox end}}
{{Starbox end}}


'''Kepler-14''' is a [[binary star]] system targeted by the [[Kepler (spacecraft)|Kepler]] spacecraft. It is host to one known planet: the Jupiter-like [[Kepler-14b]]. The star system was identified early by Kepler as a possible planetary host, but when imaging revealed that Kepler-14 was a binary star system and not a single star, the confirmation process was protracted. The stars are separated by at least 280 AU, and the stars complete an orbit around a common center of mass every 2800 years. Both stars are larger than the Sun; they are both of similar [[absolute magnitude]]s. However, the primary star is brighter as seen from Earth.
'''Kepler-14''' is a [[binary star]] system targeted by the [[Kepler (spacecraft)|Kepler]] spacecraft. It is host to one known planet: the Jupiter-like [[Kepler-14b]]. The star system was identified by Kepler as a possible planetary host, but when imaging revealed that Kepler-14 was a binary star system and not a single star, the confirmation process became protracted. The stars are separated by at least 280 AU, and the stars complete an orbit around a common center of mass every 2800 years. Both stars are larger than the Sun. They are of similar [[absolute magnitude]]s; however, the primary star is brighter as seen from Earth.


==Observational history==
==Observational history==
[[File:PalomarObservatory.JPG|upright|left|thumb|The Palomar Observatory confirmed findings suggesting that Kepler-14 was a binary star.]]
Kepler-14 was identified as a possible host to a planet during the first four months of [[Kepler (spacecraft)|Kepler]]'s operational data, which began when [[NASA]] launched the satellite in April 2009. Kepler-14 was provisionally designated KOI-98. Because Kepler-14's transit signal seemed to imply that the possible planet had a short orbit and a clear effect on Kepler-14's brightness, the Kepler science team forwarded the candidate to the [[Kepler Follow-up Program]] (KFOP).<ref name="Buchhave2011"/>


KFOP used the Fibre-fed Échelle Spectrograph (FIES) on the [[Nordic Optical Telescope]] to measure Kepler-14's [[radial velocity]] in October 2009. Other radial velocity measurements were collected using [[W.M. Keck Observatory]]. The FIES and Keck data, combined with [[speckle imaging]] data from [[WIYN Observatory]] and near-infrared [[adaptive optics]] measurements at [[Palomar Observatory]] and the [[MMT Observatory]], revealed that Kepler-14 was actually a close [[binary star]], something that radial velocity data alone could not recognize. Because of this new discovery, further investigation of Kepler-14 was postponed until after the publishing of the first five new Kepler planets (the ones orbiting [[Kepler-4]], [[Kepler-5]], [[Kepler-6]], [[Kepler-7]], and [[Kepler-8]]).<ref name="Buchhave2011"/> Analysis of the data revealed that, of the two-component stars in the Kepler-14 system, both stars are of nearly equal magnitude, although one of the stars was fainter. The brighter star was designated the "A" component, and the fainter star received the "B" designation. The transit signal was observed in orbit around the A component of the system, meaning that the planetary candidate would be in orbit of the primary star of Kepler-14. This was confirmed on August 7, 2010, when the Infrared Array Camera on the [[Spitzer Space Telescope]] observed Kepler-14 to gather [[photometry (astronomy)|photometric]] data.<ref name="Buchhave2011"/>
Kepler-14 was identified as a possible host to a planet as early as the first four months of [[Kepler (spacecraft)|Kepler]]'s operational data, which began when [[NASA]] launched the satellite in April 2009. Kepler-14 was provisionally designated KOI-98. Because Kepler-14's transit signal seemed to imply that the possible planet had a short orbit and a clear effect on Kepler-14's brightness, the Kepler science team forwarded the candidate to the [[Kepler Follow-up Program]] (KFOP).<ref name=Buchhave2011 />
Analysis of both the Spitzer photometric data and the radial velocity data confirmed the idea of a planet as the source of the transit signal.<ref name="Buchhave2011"/> The planet was designated [[Kepler-14b]], and this was published alongside the data and research on Kepler-14 in a June 2011 paper.<ref name="Buchhave2011"/>


Kepler-14's nature as a close binary star was almost missed by the astronomers, and would not have been known if high-resolution imaging of the star had not been undertaken. The Kepler team acknowledged that a number of transiting planets' host stars may have actually been close visual binaries and that the assumed characteristics of the stars and their planets may be incorrect. As a result of their studies into Kepler-14, the Kepler team suggested the implementation of a high-resolution imaging campaign to re-examine transiting planet hosts, an effort that would require only a modest amount of telescope time.<ref name="Buchhave2011"/>
KFOP used the Fibre-fed Échelle Spectrograph (FIES) on the [[Nordic Optical Telescope]] to measure Kepler-14's [[radial velocity]] in October 2009. Other radial velocity measurements were collected using [[W.M. Keck Observatory]]. The FIES and Keck data, combined with [[speckle imaging]] data from [[WIYN Observatory]] and near-infrared [[adaptive optics]] measurements at [[Palomar Observatory]] and the [[MMT Observatory]], revealed that Kepler-14 was actually a closely knit [[binary star]], something that radial velocity data alone could not recognize. Because of this new discovery, further investigation of Kepler-14 was postponed until after the publishing of the first five new Kepler planets (the ones orbiting [[Kepler-4]], [[Kepler-5]], [[Kepler-6]], [[Kepler-7]], and [[Kepler-8]]).<ref name=Buchhave2011 /> Analysis of the collected data revealed that, of the two component stars in the Kepler-14 system, both stars are of nearly equal magnitude, although one of the stars was fainter. The brighter star was designated the "A" component, and the fainter star received the "B" designation. The transit signal was also observed in orbit around the A component of the system, meaning that the planetary candidate would be in orbit of the primary star of Kepler-14. On August 7, 2010, the Infrared Array Camera on the [[Spitzer Space Telescope]] observed Kepler-14 to gather [[photometry (astronomy)|photometric]] data. The photometric data confirmed this idea.<ref name=Buchhave2011 />
[[File:Spitzer- Telescopio.jpg|200px|left|thumb|The Spitzer Space Telescope (prior to launch), responsible for collecting photometric data on Kepler-14.]]
Analysis of both the Spitzer photometric data and the radial velocity data confirmed the idea of a planet as the source of the transit signal.<ref name=Buchhave2011 /> The planet was designated [[Kepler-14b]], and was published alongside the data and research on Kepler-14 in a June 2011 paper.<ref name=ArXiv /> In the discovery paper, Kepler-14's nature as a close binary star was almost missed by the astronomers, and would not have been known if high-resolution imaging of the star had not been undertaken. The Kepler team acknowledged that a number of transiting planets' host stars may have actually been close visual binaries, and that (as a result) the characteristics of the stars and their planets may be incorrect. As a result of their studies into Kepler-14, the Kepler team suggested the implementation of a high-resolution imaging campaign to re-examine transiting planet hosts, an effort which would only require a modest amount of telescope time.<ref name=Buchhave2011 />


==Characteristics==
==Characteristics==
Kepler-14 is a binary star whose two components are separated by at least 280 [[astronomical unit]]s, or the distance between the Earth and Sun.<ref name="Buchhave2011"/> The estimated [[orbital period]] of the Kepler-14 binary system is approximated at 2800 years.<ref name=Buchhave2011/> The two stars are of nearly equal brightness, but the primary component is slightly brighter as it has a more visible [[apparent magnitude]], or its brightness as seen from Earth.<ref name="Buchhave2011"/> The primary star has an estimated mass of 1.51 [[solar mass|times that of the Sun]], and the secondary has an estimated mass of 1.39 times the Sun's mass.<ref name="Buchhave2011"/> The Kepler-14 system is 980 [[parsec]]s (3,196 [[light year]]s) from Earth. It has an [[apparent magnitude]] of 12.12, and thus cannot be seen with the unaided eye.<ref name=datatable />


Because Kepler-14 is so close-knit as seen from Earth, it was impossible for the discovery team to separate the two stars and analyze their characteristics as separate stars. The Kepler team analyzed their characteristics under the assumption that Kepler-14 was a single star.<ref name="Buchhave2011"/>
Kepler-14 is a binary star whose two components are separated by at least 280 [[astronomical unit|distances between the Earth and Sun]]. The estimated [[orbital period]] of the Kepler-14 binary system is approximated at 2800 years The two stars are of nearly equal brightness, but the primary component is slightly brighter as seen from Earth. The primary star has an estimated mass of 1.51 [[solar mass|times that of the Sun]], and the secondary has an estimated mass of 1.39 times the Sun's mass.<ref name=Buchhave2011 />

Because Kepler-14 is so close-knit as seen fron Earth, it was impossible for the discovery team to separate the two stars and analyze their characteristics as separate stars. The Kepler team analyzed their characteristics anyways under the assumption that Kepler-14 was a single star.<ref name=Buchhave2011 /> Kepler-14 is a binary star whose two components are separated by at least 280 [[astronomical unit|distances between the Earth and Sun]]. The estimated [[orbital period]] of the Kepler-14 binary system is approximated at 2800 years The two stars are of nearly equal brightness, but the primary component is slightly brighter as seen from Earth. The primary star has an estimated mass of 1.51 [[solar mass|times that of the Sun]], and the secondary has an estimated mass of 1.39 times the Sun's mass.<ref name=Buchhave2011></ref> The Kepler-14 system is 980 [[parsec]]s (3,196 [[light year]]s) from Earth. It has an [[apparent magnitude]] of 12.12, and thus cannot be seen with the unaided eye.<ref name=datatable />

Because Kepler-14 is so close-knit as seen fron Earth, it was impossible for the discovery team to separate the two stars and analyze their characteristics as separate stars. The Kepler team analyzed their characteristics anyways under the assumption that Kepler-14 was a single star.<ref name=Buchhave2011></ref>

If Kepler-14 were a single star, it would be an [[Stellar classification#Class F|F-type]] star with a mass of 1.512 times the Sun's, and a size that is 2.048 times the [[solar radius|Sun's radius]]. As a single star, the [[effective temperature]] of Kepler-14 would be 6395 [[Kelvin scale|K]], much hotter than the Sun, and the star's [[metallicity|iron content]] would be 0.12, or 132% the amount found in the Sun. Assuming that Kepler-14's two stars formed at about the same time, their [[gyrochronological age]]s would be approximately 2.2 billion years.<ref name=EPE />
If Kepler-14 were a single star, it would be an [[Stellar classification#Class F|F-type]] star with a mass of 1.512 times the Sun's, and a size that is 2.048 times the [[solar radius|Sun's radius]]. As a single star, the [[effective temperature]] of Kepler-14 would be 6395 [[Kelvin scale|K]], much hotter than the Sun, and the star's [[metallicity|iron content]] would be 0.12, or 132% the amount found in the Sun. Assuming that Kepler-14's two stars formed at about the same time, their [[gyrochronological age]]s would be approximately 2.2 billion years.<ref name=EPE />
==Planetary system==


==Planetary system==
{{main|Kepler-14b}}
{{main|Kepler-14b}}
Kepler-14b is a [[Jupiter]]-like planet in the orbit of the primary star of Kepler-14. The planet is 8.4 times [[Jupiter mass|Jupiter's mass]], the equivalent of 2670 times Earth's mass. The planet is slightly larger than Jupiter at 1.14 [[Jupiter radius|Jupiter radii]]<ref name=datatable /> The density of Kepler-14b is 7.1 grams/cm<sup>3</sup>, the second densest planet confirmed by the Kepler spacecraft after [[Kepler-10b]].<ref name=datatable /> Kepler-14b completes an orbit every 6.79 days with a slightly irregular orbit indicated its [[orbital eccentricity]] of 0.035.<ref name=datatable />
Kepler-14b is a [[Jupiter]]-like planet in the orbit of the primary star of Kepler-14. The planet is 8.4 times [[Jupiter mass|Jupiter's mass]], the equivalent of 2670 times Earth's mass. The planet is slightly larger than Jupiter at 1.14 [[Jupiter radius|Jupiter radii]]<ref name=datatable /> The density of Kepler-14b is {{val|7.1|u=g/cm3}}, the second densest planet confirmed by the Kepler spacecraft after [[Kepler-10b]].<ref name=datatable /> Kepler-14b completes an orbit every 6.79 days with a slightly irregular orbit indicated by its [[orbital eccentricity]] of 0.035.<ref name=datatable />

Radial velocity measurements of host star did not reveal any additional planets as in 2018.<ref>{{citation|arxiv=1807.00549|year=2019|doi=10.3847/1538-3881/aaf22f|last1=Eylen|first1=Vincent Van|last2=Albrecht|first2=Simon|last3=Huang|first3=Xu|last4=MacDonald|first4=Mariah G.|last5=Dawson|first5=Rebekah I.|last6=Cai|first6=Maxwell X.|last7=Foreman-Mackey|first7=Daniel|last8=Lundkvist|first8=Mia S.|last9=Aguirre|first9=Victor Silva|last10=Snellen|first10=Ignas|last11=Winn|first11=Joshua N.|title=The Orbital Eccentricity of Small Planet Systems|journal=The Astronomical Journal|volume=157|issue=2|page=61|bibcode=2019AJ....157...61V|s2cid=119082221 |doi-access=free }}</ref>


{{OrbitboxPlanet begin|table_ref=<ref name="EPE"/>}}
{{OrbitboxPlanet begin
|table_ref=<ref name="EPE"/><ref name="datatable"/>}}
{{OrbitboxPlanet
{{OrbitboxPlanet
| exoplanet = [[Kepler-14b|b]]
| exoplanet = [[Kepler-14b|b]]
| mass = 8.4
| mass = 8.4
| period = {{val|6.7901236131|0.0000003985|fmt=commas}}<ref name="Battley2021"/>
| period = 6.790123
| semimajor = N/A
| eccentricity = 0.035
| eccentricity = 0.035
| inclination = ~90
| radius = 1.14
| radius = 1.14
}}
}}
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{{reflist|refs=
{{reflist|refs=


<ref name="Battley2021">{{cite journal | title=Revisiting the Kepler field with TESS: Improved ephemerides using TESS 2 min data | last1=Battley | first1=Matthew P | last2=Kunimoto | first2=Michelle | last3=Armstrong | first3=David J | last4=Pollacco | first4=Don | display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society | date=10 March 2021 | volume=503 | issue=3 | pages=4092–4104 | arxiv=2103.03259 | bibcode=2021MNRAS.503.4092B | bibcode-access=free | doi=10.1093/mnras/stab701 | doi-access=free }}</ref>
<ref name=ArXiv>{{cite arxiv |eprint=1106.5510 |author1=Buchhave |author2=Latham |author3=Carter |author4=Jean-Michel Désert |author5=Guillermo Torres |author6=Adams |author7=Bryson |author8=Charbonneau |author9=Ciardi |title=Kepler-14b: A massive hot Jupiter transiting an F star in a close visual binary |class=astro-ph.EP |year=2011}}</ref>


<ref name="Buchhave2011">{{cite journal | title=Kepler-14b: A Massive Hot Jupiter Transiting an F Star in a Close Visual Binary | last1=Buchhave | first1=Lars A. | last2=Latham | first2=David W. | last3=Carter | first3=Joshua A. | last4=Désert | first4=Jean-Michel | last5=Torres | first5=Guillermo | last6=Adams | first6=Elisabeth R. | last7=Bryson | first7=Stephen T. | last8=Charbonneau | first8=David B. | last9=Ciardi | first9=David R. | last10=Kulesa | first10=Craig | last11=Dupree | first11=Andrea K. | last12=Fischer | first12=Debra A. | last13=Fressin | first13=François | last14=Gautier | first14=Thomas N. | last15=Gilliland | first15=Ronald L. | last16=Howell | first16=Steve B. | last17=Isaacson | first17=Howard | last18=Jenkins | first18=Jon M. | last19=Marcy | first19=Geoffrey W. | last20=McCarthy | first20=Donald W. | last21=Rowe | first21=Jason F. | last22=Batalha | first22=Natalie M. | last23=Borucki | first23=William J. | last24=Brown | first24=Timothy M. | last25=Caldwell | first25=Douglas A. | last26=Christiansen | first26=Jessie L. | last27=Cochran | first27=William D. | last28=Deming | first28=Drake | last29=Dunham | first29=Edward W. | last30=Everett | first30=Mark | last31=Ford | first31=Eric B. | last32=Fortney | first32=Jonathan J. | last33=Geary | first33=John C. | last34=Girouard | first34=Forrest R. | last35=Haas | first35=Michael R. | last36=Holman | first36=Matthew J. | last37=Horch | first37=Elliott | last38=Klaus | first38=Todd C. | last39=Knutson | first39=Heather A. | last40=Koch | first40=David G. | last41=Kolodziejczak | first41=Jeffrey | last42=Lissauer | first42=Jack J. | last43=Machalek | first43=Pavel | last44=Mullally | first44=Fergal | last45=Still | first45=Martin D. | last46=Quinn | first46=Samuel N. | last47=Seager | first47=Sara | last48=Thompson | first48=Susan E. | last49=Van Cleve | first49=Jeffrey | display-authors=1 | journal=The Astrophysical Journal Supplement Series | date=28 September 2011 | volume=197 | issue=1 | article-number=3 | page=<!-- to prevent citation bot adding nonexistent page number--> | arxiv=1106.5510 | bibcode=2011ApJS..197....3B | bibcode-access=free | doi=10.1088/0067-0049/197/1/3 | doi-access=free }}</ref>
<ref name=Buchhave2011>{{cite journal |last1=Buchhave |first1=L. |last2=Latham |first2=D. |year=2011 |title=Kepler-14b: A MASSIVE HOT JUPITER TRANSITING AN F STAR IN A CLOSE VISUAL BINARY |journal=[[Astrophysical Journal]] |volume= |issue= |pages= |publisher= |doi= |arxiv=1106.5510v1 }}</ref>


<ref name=EPE>{{cite web |url=http://www.exoplanet.eu/planet.php?p1=Kepler-14&p2=b#a_publi |title=Notes for Planet Kepler-14 b |author=Jean Schneider |year=2011 |work= |publisher=[[Extrasolar Planets Encyclopaedia]] |accessdate=5 September 2011}}</ref>
<ref name=EPE>{{cite encyclopedia |url=https://exoplanet.eu/catalog/kepler-14_b/ |title=Notes for Planet Kepler-14 b |author=Jean Schneider |date=2011 |access-date=5 September 2011 |archive-url=https://web.archive.org/web/20121019011120/http://exoplanet.eu/catalog/kepler-14_b/ |archive-date=19 October 2012 |encyclopedia=[[Extrasolar Planets Encyclopaedia]] |url-status=live }}</ref>


<ref name="datatable">
<ref name="datatable">
{{cite web |url=http://kepler.nasa.gov/Mission/discoveries/ |title=Summary Table of Kepler Discoveries |date=23 July 2011 |work=[[Ames Research Center]] |publisher=NASA|accessdate=5 September 2011}}</ref>
{{cite web |url=https://exoplanetarchive.ipac.caltech.edu/cgi-bin/DisplayOverview/nph-DisplayOverview?objname=Kepler-14+b&type=CONFIRMED_PLANET|title=Confimred Planet Overview Page|work=[[Ames Research Center]] |publisher=NASA|access-date=18 April 2019}}</ref>


}}
}}


{{Stars of Lyra}}
[[Category:Binary stars]]

{{Sky|19|10|50|+|47|19|59|3196}}
{{Sky|19|10|50|+|47|19|59|3196}}


[[fr:Kepler-14]]
[[Category:Lyra]]
[[Category:Binary stars]]
[[ru:Kepler-14]]
[[Category:Planetary transit variables]]
[[Category:Kepler objects of interest|98]]
[[Category:Planetary systems with one confirmed planet]]
[[Category:2MASS objects|J19105011+4719589]]

Latest revision as of 19:16, 9 March 2024

Kepler-14
Observation data
Epoch J2000      Equinox J2000
Constellation Lyra
Right ascension 19h 10m 50.110s[1]
Declination +47° 19′ 58.87″[1]
Apparent magnitude (V) 12.00[2]
Astrometry
Proper motion (μ) RA: 1.0[1] mas/yr
Dec.: -10.2[1] mas/yr
Distance3200 ly
(980[3] pc)
Characteristics
Spectral type F[3]
Orbit
PrimaryKepler-14A
CompanionKepler-14B
Period (P)~2800[4] yr
Semi-major axis (a)280 AU[4]
Details[4]
Mass1.512 (± 0.043) M
Radius2.048 +0.112
−0.084
 R
Luminosity6.29 +0.75
−0.58
 L
Temperature6395 (± 60) K
Metallicity+0.12 (± 0.06)
Rotational velocity (v sin i)7.9 (± 1.0) km/s
Age2.2 +0.2
−0.1
 Gyr
Other designations
KOI-98, KIC 10264660, TYC 3546-413-1, GSC 03546-00413, WDS J19108+4720AB, 2MASS J19105011+4719589
Database references
SIMBADdata
KICdata

Kepler-14 is a binary star system targeted by the Kepler spacecraft. It is host to one known planet: the Jupiter-like Kepler-14b. The star system was identified by Kepler as a possible planetary host, but when imaging revealed that Kepler-14 was a binary star system and not a single star, the confirmation process became protracted. The stars are separated by at least 280 AU, and the stars complete an orbit around a common center of mass every 2800 years. Both stars are larger than the Sun. They are of similar absolute magnitudes; however, the primary star is brighter as seen from Earth.

Observational history

[edit]
The Palomar Observatory confirmed findings suggesting that Kepler-14 was a binary star.

Kepler-14 was identified as a possible host to a planet during the first four months of Kepler's operational data, which began when NASA launched the satellite in April 2009. Kepler-14 was provisionally designated KOI-98. Because Kepler-14's transit signal seemed to imply that the possible planet had a short orbit and a clear effect on Kepler-14's brightness, the Kepler science team forwarded the candidate to the Kepler Follow-up Program (KFOP).[4]

KFOP used the Fibre-fed Échelle Spectrograph (FIES) on the Nordic Optical Telescope to measure Kepler-14's radial velocity in October 2009. Other radial velocity measurements were collected using W.M. Keck Observatory. The FIES and Keck data, combined with speckle imaging data from WIYN Observatory and near-infrared adaptive optics measurements at Palomar Observatory and the MMT Observatory, revealed that Kepler-14 was actually a close binary star, something that radial velocity data alone could not recognize. Because of this new discovery, further investigation of Kepler-14 was postponed until after the publishing of the first five new Kepler planets (the ones orbiting Kepler-4, Kepler-5, Kepler-6, Kepler-7, and Kepler-8).[4] Analysis of the data revealed that, of the two-component stars in the Kepler-14 system, both stars are of nearly equal magnitude, although one of the stars was fainter. The brighter star was designated the "A" component, and the fainter star received the "B" designation. The transit signal was observed in orbit around the A component of the system, meaning that the planetary candidate would be in orbit of the primary star of Kepler-14. This was confirmed on August 7, 2010, when the Infrared Array Camera on the Spitzer Space Telescope observed Kepler-14 to gather photometric data.[4] Analysis of both the Spitzer photometric data and the radial velocity data confirmed the idea of a planet as the source of the transit signal.[4] The planet was designated Kepler-14b, and this was published alongside the data and research on Kepler-14 in a June 2011 paper.[4]

Kepler-14's nature as a close binary star was almost missed by the astronomers, and would not have been known if high-resolution imaging of the star had not been undertaken. The Kepler team acknowledged that a number of transiting planets' host stars may have actually been close visual binaries and that the assumed characteristics of the stars and their planets may be incorrect. As a result of their studies into Kepler-14, the Kepler team suggested the implementation of a high-resolution imaging campaign to re-examine transiting planet hosts, an effort that would require only a modest amount of telescope time.[4]

Characteristics

[edit]

Kepler-14 is a binary star whose two components are separated by at least 280 astronomical units, or the distance between the Earth and Sun.[4] The estimated orbital period of the Kepler-14 binary system is approximated at 2800 years.[4] The two stars are of nearly equal brightness, but the primary component is slightly brighter as it has a more visible apparent magnitude, or its brightness as seen from Earth.[4] The primary star has an estimated mass of 1.51 times that of the Sun, and the secondary has an estimated mass of 1.39 times the Sun's mass.[4] The Kepler-14 system is 980 parsecs (3,196 light years) from Earth. It has an apparent magnitude of 12.12, and thus cannot be seen with the unaided eye.[5]

Because Kepler-14 is so close-knit as seen from Earth, it was impossible for the discovery team to separate the two stars and analyze their characteristics as separate stars. The Kepler team analyzed their characteristics under the assumption that Kepler-14 was a single star.[4] If Kepler-14 were a single star, it would be an F-type star with a mass of 1.512 times the Sun's, and a size that is 2.048 times the Sun's radius. As a single star, the effective temperature of Kepler-14 would be 6395 K, much hotter than the Sun, and the star's iron content would be 0.12, or 132% the amount found in the Sun. Assuming that Kepler-14's two stars formed at about the same time, their gyrochronological ages would be approximately 2.2 billion years.[3]

Planetary system

[edit]

Kepler-14b is a Jupiter-like planet in the orbit of the primary star of Kepler-14. The planet is 8.4 times Jupiter's mass, the equivalent of 2670 times Earth's mass. The planet is slightly larger than Jupiter at 1.14 Jupiter radii[5] The density of Kepler-14b is 7.1 g/cm3, the second densest planet confirmed by the Kepler spacecraft after Kepler-10b.[5] Kepler-14b completes an orbit every 6.79 days with a slightly irregular orbit indicated by its orbital eccentricity of 0.035.[5]

Radial velocity measurements of host star did not reveal any additional planets as in 2018.[6]

The Kepler-14 planetary system[3][5]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b 8.4 MJ 6.7901236131±0.0000003985[7] 0.035 ~90° 1.14 RJ

References

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  1. ^ a b c d Zacharias, N. (2009). "Third U.S. Naval Observatory CCD Astrograph Catalog (UCAC3)". VizieR On-line Data Catalog. Bibcode:2009yCat.1315....0Z.
  2. ^ Høg, E.; et al. (2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H.
  3. ^ a b c d Jean Schneider (2011). "Notes for Planet Kepler-14 b". Extrasolar Planets Encyclopaedia. Archived from the original on 19 October 2012. Retrieved 5 September 2011.
  4. ^ a b c d e f g h i j k l m n Buchhave, Lars A.; et al. (28 September 2011). "Kepler-14b: A Massive Hot Jupiter Transiting an F Star in a Close Visual Binary". The Astrophysical Journal Supplement Series. 197 (1) 3. arXiv:1106.5510. Bibcode:2011ApJS..197....3B. doi:10.1088/0067-0049/197/1/3.
  5. ^ a b c d e "Confimred Planet Overview Page". Ames Research Center. NASA. Retrieved 18 April 2019.
  6. ^ Eylen, Vincent Van; Albrecht, Simon; Huang, Xu; MacDonald, Mariah G.; Dawson, Rebekah I.; Cai, Maxwell X.; Foreman-Mackey, Daniel; Lundkvist, Mia S.; Aguirre, Victor Silva; Snellen, Ignas; Winn, Joshua N. (2019), "The Orbital Eccentricity of Small Planet Systems", The Astronomical Journal, 157 (2): 61, arXiv:1807.00549, Bibcode:2019AJ....157...61V, doi:10.3847/1538-3881/aaf22f, S2CID 119082221
  7. ^ Battley, Matthew P; et al. (10 March 2021). "Revisiting the Kepler field with TESS: Improved ephemerides using TESS 2 min data". Monthly Notices of the Royal Astronomical Society. 503 (3): 4092–4104. arXiv:2103.03259. Bibcode:2021MNRAS.503.4092B. doi:10.1093/mnras/stab701.