HD 233731#Planetary system

{{short description|Suspected multiple star system in the constellation Ursa Major}}

{{Starbox observe

| epoch = J2000

| constell = Ursa Major

| ra = {{RA|10|22|43.5923}}

| dec = {{DEC|+50|07|42.062}}

| appmag_v = 9.732

}}

{{Starbox character

| type =

| class = G5V

| b-v = 0.86

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{val|12.86|(15)}}

| prop_mo_ra = {{val|−26.110|(14)}}

| prop_mo_dec = {{val|83.806|(16)}}

| pm_footnote =

| parallax = 12.2731

| p_error = 0.0155

| parallax_footnote =

| absmag_v = {{val|5.22|0.14}}

}}

{{Starbox detail

| source =

| mass = {{val|0.936|0.028|0.033}}

| radius = {{val|1.062|0.046|0.013}}

| gravity = {{val|4.357|0.039|0.005}}

| luminosity = {{val|0.77|0.09}}

| temperature = {{val|5314|50|fmt=commas}}

| metal_fe = {{val|0.30|0.09}}

| rotation = {{val|28.7|0.4|u=days}}

| rotational_velocity = {{val|1.65|0.26}}

| age_gyr = {{val|9.0|1.4|2.2|u=Gyr}}
{{val|12.4|2.6}}

}}

{{Starbox catalog

| names = {{odlist | name=HAT-P-22 | HD=233731 | GSC=03441-00925 | 2MASS=J10224361+5007420 | TYC=3441-925-1 | Gaia DR2=846946629987527168 }}

}}

{{Starbox reference

| Simbad = HD+233731

}}

HD 233731, or HAT-P-22, is a suspected multiple star system in the northern circumpolar constellation of Ursa Major. It is invisible to the naked eye, having an apparent visual magnitude of 9.732. This system is located at a distance of 267 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +13 km/s.

The stellar classification of the primary is G5V, matching an ordinary G-type main-sequence star. The star has a low level of stellar activity with an estimated age of 9 to 12 billion years old. Its metallicity is twice that of the Sun, unusual for its advanced age. HD 233731 has a similar mass and radius as the Sun, and is spinning with a rotation period of 28.7 days. It is radiating 77% of the luminosity of the Sun from its photosphere at an effective temperature of 5314 K.

A faint stellar companion (2MASS J10224397+5007504) with a red hue is located at an angular separation of {{val|9|u=arcseconds}} from the primary. In 2015, a spectroscopic stellar companion was reported with a semimajor axis of less than {{val|33|ul=AU}}. This star has an effective temperature of {{val|4000|250|400|fmt=commas|u=K}} with a mass of {{val|0.63|0.07|0.17|u=solar mass}}.

Planetary system

In 2010 a transiting hot Jupiter like planet was detected, designated HAT-P-22b. It has an equilibrium temperature of {{val|1463|19|u=K|fmt=commas}}, and planetary atmosphere is cloudy. The measurement of Rossiter-McLaughlin effect in 2018 has allowed to detect what the planetary orbit is well aligned with the equatorial plane of the star, with a misalignment angle equal to {{val|25|18|u=°}}.

In 2017, analysis of additional HARPS data showed a long-term trend that suggested the presence of an additional orbiting companion, HAT-P-22c.

File:Exoplanet Comparison HAT-P-22 b.png

{{OrbitboxPlanet begin

| name = HAT-P-22

| table_ref =

}}

{{OrbitboxPlanet

| exoplanet = b

| mass = 2.192{{±|0.073|0.013}}

| radius = 1.060{{±|0.048}}

| semimajor = 0.04171{{±|0.00042|0.00050}}

| period = 3.21223328

| eccentricity = 0.016{{±|0.009}}

| inclination = 86.46{{±|0.41}}

}}

{{OrbitboxPlanet hypothetical

| exoplanet = c

| mass = {{val|3.0|p=≥}}

| period = {{val|20.8|u=years|p=≥}}

}}

References

{{Reflist|refs=

{{cite simbad

| title=HD 233731

| access-date=2015-12-10

| postscript=.

}}

{{citation | postscript=.

| title=Friends of Hot Jupiters. III. An Infrared Spectroscopic Search for Low-Mass Stellar Companions

| last1=Piskorz | first1=Danielle | last2=Knutson | first2=Heather A.

| last3=Ngo | first3=Henry | last4=Muirhead | first4=Philip S.

| last5=Batygin | first5=Konstantin | last6=Crepp | first6=Justin R.

| last7=Hinkley | first7=Sasha | last8=Morton | first8=Timothy D.

| display-authors=1 | journal=The Astrophysical Journal

| volume=814 | issue=2 | page=148 | year=2015

| arxiv=1510.08062 | bibcode=2015ApJ...814..148P

| doi=10.1088/0004-637X/814/2/148 | s2cid=11525988 }}

{{citation | postscript=.

| title=Ground-based near-UV observations of 15 transiting exoplanets: Constraints on their atmospheres and no evidence for asymmetrical transits

| last1=Turner | first1=Jake D. | last2=Pearson | first2=Kyle A.

| last3=Biddle | first3=Lauren I. | last4=Smart | first4=Brianna M.

| last5=Zellem | first5=Robert T. | last6=Teske | first6=Johanna K.

| last7=Hardegree-Ullman | first7=Kevin K. | last8=Griffith | first8=Caitlin C.

| last9=Leiter | first9=Robin M. | last10=Cates | first10=Ian T.

| last11=Nieberding | first11=Megan N. | last12=Smith | first12=Carter-Thaxton W.

| last13=Thompson | first13=Robert M. | last14=Hofmann | first14=Ryan

| last15=Berube | first15=Michael P. | last16=Nguyen | first16=Chi H.

| last17=Small | first17=Lindsay C. | last18=Guvenen | first18=Blythe C.

| last19=Richardson | first19=Logan | last20=McGraw | first20=Allison

| last21=Raphael | first21=Brandon | last22=Crawford | first22=Benjamin E.

| last23=Robertson | first23=Amy N. | last24=Tombleson | first24=Ryan

| last25=Carleton | first25=Timothy M. | last26=Towner | first26=Allison P.M.

| last27=Walker-Lafollette | first27=Amanda M. | last28=Hume | first28=Jeffrey R.

| last29=Watson | first29=Zachary T. | last30=Jones | first30=Christen K.

| display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society

| volume=459 | pages=789–819 | year=2016

| issue=1

| doi=10.1093/mnras/stw574 | doi-access=free

| s2cid=8769245

| arxiv=1603.02587 | bibcode=2016MNRAS.459..789T }}

{{citation | postscript=.

| title=The GAPS programme with HARPS-N at TNG XVI. Measurement of the Rossiter-McLaughlin effect of transiting planetary systems HAT-P-3, HAT-P-12, HAT-P-22, WASP-39, and WASP-60

| last1=Mancini | first1=L. | last2=Esposito | first2=M.

| last3=Covino | first3=E. | last4=Southworth | first4=J.

| last5=Biazzo | first5=K. | last6=Bruni | first6=I.

| last7=Ciceri | first7=S. | last8=Evans | first8=D.

| last9=Lanza | first9=A. F. | last10=Poretti | first10=E.

| last11=Sarkis | first11=P. | last12=Smith | first12=A. M. S.

| last13=Brogi | first13=M. | last14=Affer | first14=L.

| last15=Benatti | first15=S. | last16=Bignamini | first16=A.

| last17=Boccato | first17=C. | last18=Bonomo | first18=A. S.

| last19=Borsa | first19=F. | last20=Carleo | first20=I.

| last21=Claudi | first21=R. | last22=Cosentino | first22=R.

| last23=Damasso | first23=M. | last24=Desidera | first24=S.

| last25=Giacobbe | first25=P. | last26=Gonzalez-Alvarez | first26=E.

| last27=Gratton | first27=R. | last28=Harutyunyan | first28=A.

| last29=Leto | first29=G. | last30=Maggio | first30=A.

| display-authors=1 | journal=Astronomy & Astrophysics

| volume=A41 | page=613 | year=2018

| doi=10.1051/0004-6361/201732234 | s2cid=73565379

| arxiv=1802.03859 | bibcode=2018A&A...613A..41M }}

{{citation | postscript=.

| title=HAT-P-20b – HAT-P-23b: Four Massive Transiting Extrasolar Planets

| last1=Bakos | first1=G. Á. | last2=Hartman | first2=J.

| last3=Torres | first3=G. | last4=Latham | first4=D. W.

| last5=Kovács | first5=Géza | last6=Noyes | first6=R. W.

| last7=Fischer | first7=D. A. | last8=Johnson | first8=J. A.

| last9=Marcy | first9=G. W. | last10=Howard | first10=A. W.

| last11=Kipping | first11=D. | last12=Esquerdo | first12=G. A.

| last13=Shporer | first13=A. | last14=Béky | first14=B.

| last15=Buchhave | first15=L. A. | last16=Perumpilly | first16=G.

| last17=Everett | first17=M. | last18=Sasselov | first18=D. D.

| last19=Stefanik | first19=R. P. | last20=Lázár | first20=J.

| last21=Papp | first21=I. | last22=Sári | first22=P.

| display-authors=1 | journal=The Astrophysical Journal

| volume=742 | issue=2 | page=116 | year=2010

| doi=10.1088/0004-637X/742/2/116 | arxiv=1008.3388

| s2cid=119182075 | bibcode=2011ApJ...742..116B }}

{{citation | postscript=.

| title=The GAPS Programme with HARPS-N at TNG. XIV. Investigating giant planet migration history via improved eccentricity and mass determination for 231 transiting planets

| display-authors=1 | last1=Bonomo | first1=A. S.

| last2=Desidera | first2=S. | last3=Benatti | first3=S.

| last4=Borsa | first4=F. | last5=Crespi | first5=S.

| last6=Damasso | first6=M. | last7=Lanza | first7=A. F.

| last8=Sozzetti | first8=A. | last9=Lodato | first9=G.

| last10=Marzari | first10=F. | last11=Boccato | first11=C.

| last12=Claudi | first12=R. U. | last13=Cosentino | first13=R.

| last14=Covino | first14=E. | last15=Gratton | first15=R.

| last16=Maggio | first16=A. | last17=Micela | first17=G.

| last18=Molinari | first18=E. | last19=Pagano | first19=I.

| last20=Piotto | first20=G. | last21=Poretti | first21=E.

| last22=Smareglia | first22=R. | last23=Affer | first23=L.