KEPLER-21b: A ROCKY PLANET AROUND A V = 8.25 mag STAR
HD 179070, aka Kepler-21, is a V = 8.25 F6IV star and the brightest exoplanet host discovered by Kepler . An early detailed analysis by Howell et al. of the first 13 months (Q0–Q5) of Kepler light curves revealed transits of a planetary companion, Kepler-21b, with a radius of about 1.60 ± 0.04 and...
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| Veröffentlicht in: | The Astronomical journal 2016-12, Vol.152 (6), p.204 |
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| creator | López-Morales, Mercedes Haywood, Raphaëlle D. Coughlin, Jeffrey L. Zeng, Li Buchhave, Lars A. Giles, Helen A. C. Affer, Laura Bonomo, Aldo S. Charbonneau, David Cameron, Andrew Collier Consentino, Rosario Dressing, Courtney D. Dumusque, Xavier Figueira, Pedro Fiorenzano, Aldo F. M. Harutyunyan, Avet Johnson, John Asher Latham, David W. Lopez, Eric D. Lovis, Christophe Malavolta, Luca Mayor, Michel Micela, Giusi Molinari, Emilio Mortier, Annelies Motalebi, Fatemeh Nascimbeni, Valerio Pepe, Francesco Phillips, David F. Piotto, Giampaolo Pollacco, Don Queloz, Didier Rice, Ken Sasselov, Dimitar Segransan, Damien Sozzetti, Alessandro Udry, Stephane Vanderburg, Andrew Watson, Chris |
| description | HD 179070,
aka
Kepler-21, is a
V
= 8.25 F6IV star and the brightest exoplanet host discovered by
Kepler
. An early detailed analysis by Howell et al. of the first 13 months (Q0–Q5) of
Kepler
light curves revealed transits of a planetary companion, Kepler-21b, with a radius of about 1.60 ± 0.04
and an orbital period of about 2.7857 days. However, they could not determine the mass of the planet from the initial radial velocity (RV) observations with Keck-HIRES, and were only able to impose a 2
σ
upper limit of 10
. Here, we present results from the analysis of 82 new RV observations of this system obtained with HARPS-N, together with the existing 14 HIRES data points. We detect the Doppler signal of Kepler-21b with a RV semiamplitude
K
= 2.00 ± 0.65
, which corresponds to a planetary mass of 5.1 ± 1.7
. We also measure an improved radius for the planet of 1.639 +0.019/−0.015
, in agreement with the radius reported by Howell et al. We conclude that Kepler-21b, with a density of 6.4 ± 2.1
, belongs to the population of small, ≲6
planets with iron and magnesium silicate interiors, which have lost the majority of their envelope volatiles via stellar winds or gravitational escape. The RV analysis presented in this paper serves as an example of the type of analysis that will be necessary to confirm the masses of TESS small planet candidates. |
| doi_str_mv | 10.3847/0004-6256/152/6/204 |
| format | Article |
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aka
Kepler-21, is a
V
= 8.25 F6IV star and the brightest exoplanet host discovered by
Kepler
. An early detailed analysis by Howell et al. of the first 13 months (Q0–Q5) of
Kepler
light curves revealed transits of a planetary companion, Kepler-21b, with a radius of about 1.60 ± 0.04
and an orbital period of about 2.7857 days. However, they could not determine the mass of the planet from the initial radial velocity (RV) observations with Keck-HIRES, and were only able to impose a 2
σ
upper limit of 10
. Here, we present results from the analysis of 82 new RV observations of this system obtained with HARPS-N, together with the existing 14 HIRES data points. We detect the Doppler signal of Kepler-21b with a RV semiamplitude
K
= 2.00 ± 0.65
, which corresponds to a planetary mass of 5.1 ± 1.7
. We also measure an improved radius for the planet of 1.639 +0.019/−0.015
, in agreement with the radius reported by Howell et al. We conclude that Kepler-21b, with a density of 6.4 ± 2.1
, belongs to the population of small, ≲6
planets with iron and magnesium silicate interiors, which have lost the majority of their envelope volatiles via stellar winds or gravitational escape. The RV analysis presented in this paper serves as an example of the type of analysis that will be necessary to confirm the masses of TESS small planet candidates.</description><identifier>ISSN: 0004-6256</identifier><identifier>ISSN: 1538-3881</identifier><identifier>EISSN: 1538-3881</identifier><identifier>DOI: 10.3847/0004-6256/152/6/204</identifier><language>eng</language><publisher>United States</publisher><subject>ASTROPHYSICS, COSMOLOGY AND ASTRONOMY ; IRON ; MAGNESIUM SILICATES ; RADIAL VELOCITY ; SATELLITES ; STARS ; STELLAR WINDS ; VOLATILITY</subject><ispartof>The Astronomical journal, 2016-12, Vol.152 (6), p.204</ispartof><lds50>peer_reviewed</lds50><oa>free_for_read</oa><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-a411t-d6fbb2ea743d3dac4ac5bf3d59cb15d7075cbee314e653027c6dcc8759814ba83</citedby><cites>FETCH-LOGICAL-a411t-d6fbb2ea743d3dac4ac5bf3d59cb15d7075cbee314e653027c6dcc8759814ba83</cites><orcidid>0000-0001-9850-9697 ; 0000-0002-3012-0316 ; 0000-0002-9937-6387 ; 0000-0003-1634-9672 ; 0000-0002-9003-484X ; 0000-0002-1742-7735 ; 0000-0003-3204-8183 ; 0000-0002-9332-2011 ; 0000-0002-7504-365X ; 0000-0001-7014-1771 ; 0000-0001-8189-0233 ; 0000-0002-8863-7828 ; 0000-0001-7246-5438 ; 0000-0001-9911-7388 ; 0000-0002-6492-2085</orcidid></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>230,314,776,780,881,27901,27902</link.rule.ids><backlink>$$Uhttps://www.osti.gov/biblio/22862832$$D View this record in Osti.gov$$Hfree_for_read</backlink></links><search><creatorcontrib>López-Morales, Mercedes</creatorcontrib><creatorcontrib>Haywood, Raphaëlle D.</creatorcontrib><creatorcontrib>Coughlin, Jeffrey L.</creatorcontrib><creatorcontrib>Zeng, Li</creatorcontrib><creatorcontrib>Buchhave, Lars A.</creatorcontrib><creatorcontrib>Giles, Helen A. C.</creatorcontrib><creatorcontrib>Affer, Laura</creatorcontrib><creatorcontrib>Bonomo, Aldo S.</creatorcontrib><creatorcontrib>Charbonneau, David</creatorcontrib><creatorcontrib>Cameron, Andrew Collier</creatorcontrib><creatorcontrib>Consentino, Rosario</creatorcontrib><creatorcontrib>Dressing, Courtney D.</creatorcontrib><creatorcontrib>Dumusque, Xavier</creatorcontrib><creatorcontrib>Figueira, Pedro</creatorcontrib><creatorcontrib>Fiorenzano, Aldo F. M.</creatorcontrib><creatorcontrib>Harutyunyan, Avet</creatorcontrib><creatorcontrib>Johnson, John Asher</creatorcontrib><creatorcontrib>Latham, David W.</creatorcontrib><creatorcontrib>Lopez, Eric D.</creatorcontrib><creatorcontrib>Lovis, Christophe</creatorcontrib><creatorcontrib>Malavolta, Luca</creatorcontrib><creatorcontrib>Mayor, Michel</creatorcontrib><creatorcontrib>Micela, Giusi</creatorcontrib><creatorcontrib>Molinari, Emilio</creatorcontrib><creatorcontrib>Mortier, Annelies</creatorcontrib><creatorcontrib>Motalebi, Fatemeh</creatorcontrib><creatorcontrib>Nascimbeni, Valerio</creatorcontrib><creatorcontrib>Pepe, Francesco</creatorcontrib><creatorcontrib>Phillips, David F.</creatorcontrib><creatorcontrib>Piotto, Giampaolo</creatorcontrib><creatorcontrib>Pollacco, Don</creatorcontrib><creatorcontrib>Queloz, Didier</creatorcontrib><creatorcontrib>Rice, Ken</creatorcontrib><creatorcontrib>Sasselov, Dimitar</creatorcontrib><creatorcontrib>Segransan, Damien</creatorcontrib><creatorcontrib>Sozzetti, Alessandro</creatorcontrib><creatorcontrib>Udry, Stephane</creatorcontrib><creatorcontrib>Vanderburg, Andrew</creatorcontrib><creatorcontrib>Watson, Chris</creatorcontrib><title>KEPLER-21b: A ROCKY PLANET AROUND A V = 8.25 mag STAR</title><title>The Astronomical journal</title><description>HD 179070,
aka
Kepler-21, is a
V
= 8.25 F6IV star and the brightest exoplanet host discovered by
Kepler
. An early detailed analysis by Howell et al. of the first 13 months (Q0–Q5) of
Kepler
light curves revealed transits of a planetary companion, Kepler-21b, with a radius of about 1.60 ± 0.04
and an orbital period of about 2.7857 days. However, they could not determine the mass of the planet from the initial radial velocity (RV) observations with Keck-HIRES, and were only able to impose a 2
σ
upper limit of 10
. Here, we present results from the analysis of 82 new RV observations of this system obtained with HARPS-N, together with the existing 14 HIRES data points. We detect the Doppler signal of Kepler-21b with a RV semiamplitude
K
= 2.00 ± 0.65
, which corresponds to a planetary mass of 5.1 ± 1.7
. We also measure an improved radius for the planet of 1.639 +0.019/−0.015
, in agreement with the radius reported by Howell et al. We conclude that Kepler-21b, with a density of 6.4 ± 2.1
, belongs to the population of small, ≲6
planets with iron and magnesium silicate interiors, which have lost the majority of their envelope volatiles via stellar winds or gravitational escape. The RV analysis presented in this paper serves as an example of the type of analysis that will be necessary to confirm the masses of TESS small planet candidates.</description><subject>ASTROPHYSICS, COSMOLOGY AND ASTRONOMY</subject><subject>IRON</subject><subject>MAGNESIUM SILICATES</subject><subject>RADIAL VELOCITY</subject><subject>SATELLITES</subject><subject>STARS</subject><subject>STELLAR WINDS</subject><subject>VOLATILITY</subject><issn>0004-6256</issn><issn>1538-3881</issn><issn>1538-3881</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2016</creationdate><recordtype>article</recordtype><recordid>eNo9kMtKw0AYhQdRMFafwE3AdZr5517BRajxQkNbYiu4GmYmE43YRjLZ-DZ9lj6ZKRVXBw4fB86H0DXgMVVMphhjlgjCRQqcpCIlmJ2gCDhVCVUKTlH0T5yjixA-MQZQmEVIzvJlkZcJAXsbZ3G5mM7e4mWRzfNVnJWL9fx-aF_3u7v9To0JjzfmPX5ZZeUlOqvNV_BXfzlC64d8NX1KisXj8zQrEsMA-qQStbXEG8loRSvjmHHc1rTiE2eBVxJL7qz3FJgXnGIinaicU5JPFDBrFB2hm-NuG_pGB9f03n24drv1rteEKEEUJQNFj5Tr2hA6X-vvrtmY7kcD1gdD-vBfH_7rwZAWejBEfwGzpVQ_</recordid><startdate>20161201</startdate><enddate>20161201</enddate><creator>López-Morales, Mercedes</creator><creator>Haywood, Raphaëlle D.</creator><creator>Coughlin, Jeffrey L.</creator><creator>Zeng, Li</creator><creator>Buchhave, Lars A.</creator><creator>Giles, Helen A. C.</creator><creator>Affer, Laura</creator><creator>Bonomo, Aldo S.</creator><creator>Charbonneau, David</creator><creator>Cameron, Andrew Collier</creator><creator>Consentino, Rosario</creator><creator>Dressing, Courtney D.</creator><creator>Dumusque, Xavier</creator><creator>Figueira, Pedro</creator><creator>Fiorenzano, Aldo F. M.</creator><creator>Harutyunyan, Avet</creator><creator>Johnson, John Asher</creator><creator>Latham, David W.</creator><creator>Lopez, Eric D.</creator><creator>Lovis, Christophe</creator><creator>Malavolta, Luca</creator><creator>Mayor, Michel</creator><creator>Micela, Giusi</creator><creator>Molinari, Emilio</creator><creator>Mortier, Annelies</creator><creator>Motalebi, Fatemeh</creator><creator>Nascimbeni, Valerio</creator><creator>Pepe, Francesco</creator><creator>Phillips, David F.</creator><creator>Piotto, Giampaolo</creator><creator>Pollacco, Don</creator><creator>Queloz, Didier</creator><creator>Rice, Ken</creator><creator>Sasselov, Dimitar</creator><creator>Segransan, Damien</creator><creator>Sozzetti, Alessandro</creator><creator>Udry, Stephane</creator><creator>Vanderburg, Andrew</creator><creator>Watson, Chris</creator><scope>AAYXX</scope><scope>CITATION</scope><scope>OTOTI</scope><orcidid>https://orcid.org/0000-0001-9850-9697</orcidid><orcidid>https://orcid.org/0000-0002-3012-0316</orcidid><orcidid>https://orcid.org/0000-0002-9937-6387</orcidid><orcidid>https://orcid.org/0000-0003-1634-9672</orcidid><orcidid>https://orcid.org/0000-0002-9003-484X</orcidid><orcidid>https://orcid.org/0000-0002-1742-7735</orcidid><orcidid>https://orcid.org/0000-0003-3204-8183</orcidid><orcidid>https://orcid.org/0000-0002-9332-2011</orcidid><orcidid>https://orcid.org/0000-0002-7504-365X</orcidid><orcidid>https://orcid.org/0000-0001-7014-1771</orcidid><orcidid>https://orcid.org/0000-0001-8189-0233</orcidid><orcidid>https://orcid.org/0000-0002-8863-7828</orcidid><orcidid>https://orcid.org/0000-0001-7246-5438</orcidid><orcidid>https://orcid.org/0000-0001-9911-7388</orcidid><orcidid>https://orcid.org/0000-0002-6492-2085</orcidid></search><sort><creationdate>20161201</creationdate><title>KEPLER-21b: A ROCKY PLANET AROUND A V = 8.25 mag STAR</title><author>López-Morales, Mercedes ; Haywood, Raphaëlle D. ; Coughlin, Jeffrey L. ; Zeng, Li ; Buchhave, Lars A. ; Giles, Helen A. C. ; Affer, Laura ; Bonomo, Aldo S. ; Charbonneau, David ; Cameron, Andrew Collier ; Consentino, Rosario ; Dressing, Courtney D. ; Dumusque, Xavier ; Figueira, Pedro ; Fiorenzano, Aldo F. M. ; Harutyunyan, Avet ; Johnson, John Asher ; Latham, David W. ; Lopez, Eric D. ; Lovis, Christophe ; Malavolta, Luca ; Mayor, Michel ; Micela, Giusi ; Molinari, Emilio ; Mortier, Annelies ; Motalebi, Fatemeh ; Nascimbeni, Valerio ; Pepe, Francesco ; Phillips, David F. ; Piotto, Giampaolo ; Pollacco, Don ; Queloz, Didier ; Rice, Ken ; Sasselov, Dimitar ; Segransan, Damien ; Sozzetti, Alessandro ; Udry, Stephane ; Vanderburg, Andrew ; Watson, Chris</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-a411t-d6fbb2ea743d3dac4ac5bf3d59cb15d7075cbee314e653027c6dcc8759814ba83</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2016</creationdate><topic>ASTROPHYSICS, COSMOLOGY AND ASTRONOMY</topic><topic>IRON</topic><topic>MAGNESIUM SILICATES</topic><topic>RADIAL VELOCITY</topic><topic>SATELLITES</topic><topic>STARS</topic><topic>STELLAR WINDS</topic><topic>VOLATILITY</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>López-Morales, Mercedes</creatorcontrib><creatorcontrib>Haywood, Raphaëlle D.</creatorcontrib><creatorcontrib>Coughlin, Jeffrey L.</creatorcontrib><creatorcontrib>Zeng, Li</creatorcontrib><creatorcontrib>Buchhave, Lars A.</creatorcontrib><creatorcontrib>Giles, Helen A. 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M.</au><au>Harutyunyan, Avet</au><au>Johnson, John Asher</au><au>Latham, David W.</au><au>Lopez, Eric D.</au><au>Lovis, Christophe</au><au>Malavolta, Luca</au><au>Mayor, Michel</au><au>Micela, Giusi</au><au>Molinari, Emilio</au><au>Mortier, Annelies</au><au>Motalebi, Fatemeh</au><au>Nascimbeni, Valerio</au><au>Pepe, Francesco</au><au>Phillips, David F.</au><au>Piotto, Giampaolo</au><au>Pollacco, Don</au><au>Queloz, Didier</au><au>Rice, Ken</au><au>Sasselov, Dimitar</au><au>Segransan, Damien</au><au>Sozzetti, Alessandro</au><au>Udry, Stephane</au><au>Vanderburg, Andrew</au><au>Watson, Chris</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>KEPLER-21b: A ROCKY PLANET AROUND A V = 8.25 mag STAR</atitle><jtitle>The Astronomical journal</jtitle><date>2016-12-01</date><risdate>2016</risdate><volume>152</volume><issue>6</issue><spage>204</spage><pages>204-</pages><issn>0004-6256</issn><issn>1538-3881</issn><eissn>1538-3881</eissn><abstract>HD 179070,
aka
Kepler-21, is a
V
= 8.25 F6IV star and the brightest exoplanet host discovered by
Kepler
. An early detailed analysis by Howell et al. of the first 13 months (Q0–Q5) of
Kepler
light curves revealed transits of a planetary companion, Kepler-21b, with a radius of about 1.60 ± 0.04
and an orbital period of about 2.7857 days. However, they could not determine the mass of the planet from the initial radial velocity (RV) observations with Keck-HIRES, and were only able to impose a 2
σ
upper limit of 10
. Here, we present results from the analysis of 82 new RV observations of this system obtained with HARPS-N, together with the existing 14 HIRES data points. We detect the Doppler signal of Kepler-21b with a RV semiamplitude
K
= 2.00 ± 0.65
, which corresponds to a planetary mass of 5.1 ± 1.7
. We also measure an improved radius for the planet of 1.639 +0.019/−0.015
, in agreement with the radius reported by Howell et al. We conclude that Kepler-21b, with a density of 6.4 ± 2.1
, belongs to the population of small, ≲6
planets with iron and magnesium silicate interiors, which have lost the majority of their envelope volatiles via stellar winds or gravitational escape. The RV analysis presented in this paper serves as an example of the type of analysis that will be necessary to confirm the masses of TESS small planet candidates.</abstract><cop>United States</cop><doi>10.3847/0004-6256/152/6/204</doi><orcidid>https://orcid.org/0000-0001-9850-9697</orcidid><orcidid>https://orcid.org/0000-0002-3012-0316</orcidid><orcidid>https://orcid.org/0000-0002-9937-6387</orcidid><orcidid>https://orcid.org/0000-0003-1634-9672</orcidid><orcidid>https://orcid.org/0000-0002-9003-484X</orcidid><orcidid>https://orcid.org/0000-0002-1742-7735</orcidid><orcidid>https://orcid.org/0000-0003-3204-8183</orcidid><orcidid>https://orcid.org/0000-0002-9332-2011</orcidid><orcidid>https://orcid.org/0000-0002-7504-365X</orcidid><orcidid>https://orcid.org/0000-0001-7014-1771</orcidid><orcidid>https://orcid.org/0000-0001-8189-0233</orcidid><orcidid>https://orcid.org/0000-0002-8863-7828</orcidid><orcidid>https://orcid.org/0000-0001-7246-5438</orcidid><orcidid>https://orcid.org/0000-0001-9911-7388</orcidid><orcidid>https://orcid.org/0000-0002-6492-2085</orcidid><oa>free_for_read</oa></addata></record> |
| fulltext | fulltext |
| identifier | ISSN: 0004-6256 |
| ispartof | The Astronomical journal, 2016-12, Vol.152 (6), p.204 |
| issn | 0004-6256 1538-3881 1538-3881 |
| language | eng |
| recordid | cdi_osti_scitechconnect_22862832 |
| source | IOP Publishing Free Content; EZB-FREE-00999 freely available EZB journals; IOPscience extra; Alma/SFX Local Collection |
| subjects | ASTROPHYSICS, COSMOLOGY AND ASTRONOMY IRON MAGNESIUM SILICATES RADIAL VELOCITY SATELLITES STARS STELLAR WINDS VOLATILITY |
| title | KEPLER-21b: A ROCKY PLANET AROUND A V = 8.25 mag STAR |
| url | https://sfx.bib-bvb.de/sfx_tum?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-02-01T00%3A58%3A17IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-crossref_osti_&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=KEPLER-21b:%20A%20ROCKY%20PLANET%20AROUND%20A%20V%C2%A0=%C2%A08.25%20mag%20STAR&rft.jtitle=The%20Astronomical%20journal&rft.au=L%C3%B3pez-Morales,%20Mercedes&rft.date=2016-12-01&rft.volume=152&rft.issue=6&rft.spage=204&rft.pages=204-&rft.issn=0004-6256&rft.eissn=1538-3881&rft_id=info:doi/10.3847/0004-6256/152/6/204&rft_dat=%3Ccrossref_osti_%3E10_3847_0004_6256_152_6_204%3C/crossref_osti_%3E%3Curl%3E%3C/url%3E&disable_directlink=true&sfx.directlink=off&sfx.report_link=0&rft_id=info:oai/&rft_id=info:pmid/&rfr_iscdi=true |