Kepler-451

{{Short description|Binary star system in the constellation Cygnus}}

{{Starbox observe

| epoch = J2000

| constell = Cygnus

| ra = {{RA|19|38|32.612}}

| dec = {{RA|+46|03|59.14}}

| appmag_v = 12.69

}}

{{Starbox character

| type=

| class=sdBV+dM

}}

{{Starbox astrometry

| radial_v =

| total_v =

| prop_mo_ra = {{val|5.225|(37)}}

| prop_mo_dec = {{val|-4.405|(42)}}

| pm_footnote =

| parallax = 2.4410

| p_error = 0.0316

| parallax_footnote =

| absmag_v =

| absmag_bol =

}}

{{Starbox orbit

| reference =

| period_unitless = {{val|0.125765282|(5)|ul=d}}

| axis =

| axis_unitless = {{val|0.823|0.015|ul=solar_radius}}

| eccentricity = 0.0004

| inclination = {{val|69.45|0.20}}

| node =

| periastron =

| periarg =

| periarg_primary =

| k1 = {{val|65.7|0.6}}

}}

{{Starbox detail

| component1=Kepler-451 A

| mass={{val|0.48|0.03}}

| radius={{val|0.203|0.001}}

| temperature={{val|29564|106}}

| age_gyr=

| component2=Kepler-451 B

| mass2={{val|0.12|0.01}}

| radius2={{val|0.168|0.001}}

}}

{{Starbox catalog

|names={{odlist | 2MASS=J19383260+4603591 | Kepler=451 | KIC=9472174 | TYC=3556-3568-1}}

}}

{{Starbox reference

|Simbad= 2MASS+J19383260%2B4603591

}}

Kepler-451 (also known as 2MASS J19383260+4603591 and abbreviated to 2M1938+4603) is an eclipsing post-common envelope binary star system that comprises two stars, a pulsating subdwarf B star and a small red dwarf star. It is located about {{convert|1340|ly|pc|lk=on|abbr=off}} away in the constellation Cygnus. It has been hypothesized to host one or more exoplanets.

Planetary system

Periodic variations in the timing of this system's eclipses were detected in 2015 using data from the Kepler space telescope. It was proposed that these variations are caused by the gravitational effects of a Jupiter-mass planet, Kepler-451b, orbiting with a period of 416 days at a distance of 0.92 AU.

The existence of planets in this system is disputed. An independent study in 2020 found no evidence for Kepler-451b, ruling out the presence of any object of at least Jupiter's mass on the claimed orbit with an inclination greater than 43°. A 2022 study instead proposed a three-planet model, including the originally claimed planet as well as two other planets of similar mass with orbital periods of 43 and 1,800 days.

In general, eclipse timing variations of this type are common in post-common envelope binary systems, and their true cause remains uncertain.

{{OrbitboxPlanet begin

| table_ref =

}}

{{OrbitboxPlanet

| exoplanet = d

| mass = 1.76{{±|0.18}}

| semimajor = 0.20{{±|0.03}}

| eccentricity=0

| period = 43.0{{±|0.1}}

|inclination=

}}

{{OrbitboxPlanet

| exoplanet = b

| mass = 1.86{{±|0.05}}

| semimajor = 0.90{{±|0.04}}

| eccentricity=0.33{{±|0.05}}

| period = 406{{±|4}}

|inclination=<43

}}

{{OrbitboxPlanet

| exoplanet = c

| mass = 1.61{{±|0.14}}

| semimajor = 2.1{{±|0.2}}

| eccentricity=0.29{{±|0.07}}

| period = 1460{{±|90}}

|inclination=

}}

References

{{Reflist|refs=

{{cite journal |bibcode=2012ApJ...753..101B |title=The Rømer Delay and Mass Ratio of the SDB+dM Binary 2M 1938+4603 from Kepler Eclipse Timings |last1=Barlow |first1=Brad N. |last2=Wade |first2=Richard A. |last3=Liss |first3=Sandra E. |journal=The Astrophysical Journal |date=2012 |volume=753 |issue=2 |page=101 |doi=10.1088/0004-637X/753/2/101 |arxiv=1204.3321 }}

{{cite journal |last1=Østensen |first1=R. H. |last2=Green |first2=E. M. |display-authors=etal |date=October 2010 |title=2M1938+4603: a rich, multimode pulsating sdB star with an eclipsing dM companion observed with Kepler |journal=Monthly Notices of the Royal Astronomical Society: Letters |volume=408 |issue=1 |pages=L51–L55 |doi=10.1111/j.1745-3933.2010.00926.x |doi-access=free |arxiv=1006.4267 |bibcode=2010MNRAS.408L..51O}}

{{cite journal |last1=Baran |first1=A. S. |last2=Zola |first2=S. |display-authors=etal |date=May 2015 |title=Detection of a planet in the sdB + M dwarf binary system 2M 1938+4603 |journal=Astronomy & Astrophysics |volume=577 |issue= |pages=A146 |doi=10.1051/0004-6361/201425392 |bibcode=2015A&A...577A.146B}}

{{cite journal|arxiv=2009.02749|year=2020|title=The quest for planets around subdwarfs and white dwarfs from Kepler space telescope fields|doi=10.1051/0004-6361/202038121|last1=Krzesinski|first1=J.|last2=Blokesz|first2=A.|last3=Siwak|first3=M.|last4=Stachowski|first4=G.|journal=Astronomy & Astrophysics|volume=642|pages=A105|s2cid=221516872 |bibcode=2020A&A...642A.105K}}

{{cite journal|arxiv=2202.02118|year=2022|title=Detection of two additional circumbinary planets around Kepler-451|author1=Ekrem Murat Esmer|last2=Baştürk|first2=Özgür|author3=Selim Osman Selam|last4=Aliş|first4=Sinan|journal=Monthly Notices of the Royal Astronomical Society |volume=511 |issue=4 |pages=5207–5216 |doi=10.1093/mnras/stac357 |doi-access=free |bibcode=2022MNRAS.511.5207E}}

{{cite journal |last1=Pulley |first1=D. |last2=Sharp |first2=I. D. |last3=Mallett |first3=J. |last4=von Harrach |first4=S. |date=August 2022 |title=Eclipse timing variations in post-common envelope binaries: Are they a reliable indicator of circumbinary companions? |journal=Monthly Notices of the Royal Astronomical Society |volume=514 |issue=4 |pages=5725–5738 |doi=10.1093/mnras/stac1676 |doi-access=free |arxiv=2206.06919 |bibcode=2022MNRAS.514.5725P}}

}}

Category:Binary stars

Category:M-type main-sequence stars

Category:B-type subdwarfs

J19383260+4603591

Category:Hypothetical planetary systems

Category:Cygnus (constellation)

451