HD 43197

{{short description|Star in the constellation Canis Major}}

{{Starbox begin|name=HD 43197 / Amadioha}}

{{Starbox observe

| epoch = J2000.0

| constell = Canis Major

| ra = {{RA|06|13|35.66155}}

| dec = {{DEC|-29|53|50.1516}}

| appmag_v = 8.98

}}

{{Starbox character

| type = main sequence

| class = G8/K0 IV/V

| appmag_1_passband = B

| appmag_1 = 9.797

| appmag_2_passband = J

| appmag_2 = {{val|7.658|0.024}}

| appmag_3_passband = H

| appmag_3 = {{val|7.328|0.038}}

| appmag_4_passband = K

| appmag_4 = {{val|7.203|0.026}}

| r-i =

| v-r =

| b-v = {{val|0.817|0.022}}

| u-b =

| variable =

}}

{{Starbox astrometry

| radial_v = {{val|72.45|0.13}}

| prop_mo_ra = {{val|147.648|0.010}}

| prop_mo_dec = {{val|16.600|0.011}}

| pm_footnote =

| parallax = 16.0171

| p_error = 0.0106

| parallax_footnote =

| absmag_v = 5.24

}}

{{Starbox detail

| mass = {{val|1.02|0.02}}

| radius = {{val|0.96|0.02}}

| luminosity = {{val|0.74|0.01}}

| gravity = {{val|4.47|0.03}}

| temperature = {{val|5469|35|fmt=commas}}

| metal_fe = 0.4

| rotational_velocity = 2.18

| age_gyr = {{val|3.1|2.0}}

}}

{{Starbox catalog

| names = {{odlist | name=Amadioha | CD=−29°2884 | HD=43197 | HIP=29550 | PPM=250048 | SAO=171427 }}

}}

{{Starbox reference

| Simbad = HD+43197

| NSTED = HD 43197

| EPE = HD+43197

}}

{{Starbox end}}

HD 43197 is a star with an exoplanetary companion in the southern constellation of Canis Major. It has been given the proper name Amadioha, as selected by Nigeria during the NameExoWorlds campaign that celebrated the 100th anniversary of the IAU. Amadioha is the god of thunder in Igbo mythology. It has an apparent visual magnitude of 8.98, meaning this is a ninth magnitude star that is too dim to be visible to the naked eye. The system is located at a distance of 204 light-years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +72 km/s. It made its closest approach some 583,000 years ago when it came to within {{convert|26.76|pc|ly|0|disp=out|abbr=off}}.

The stellar classification of this star is G8/K0 IV/V, which may be interpreted to mean the spectrum is intermediate between similar stars of class G8 and K0, and its luminosity class showing a blend of a main sequence star (V) and a subgiant star (IV). It is a weakly active star with a high metallicity, being five halves as much as the Sun. The star is about the same mass and size as the Sun, although the luminosity is only 74% of solar. The star's age is estimated to be at least three billion years and it is modelled to be right at the end of its main sequence life.

Planetary system

In 2009, the HARPS planet search program announced a Jovian planet in a highly eccentric orbit around the star. The planet spends ~78% of its orbital period in the habitable zone of the host star, although temperatures can reach {{val|716|u=K}} during periastron passage. In 2022, a second super-Jovian planet was discovered using a combination of radial velocity and astrometry. Assuming the inner planet shares the outer planet's orbital inclination, its true mass would be about {{Jupiter mass|4|link=y}}.

{{OrbitboxPlanet begin

| table_ref =

}}

{{OrbitboxPlanet

| exoplanet = b (Equiano)

| mass = {{val|0.553|0.052|0.048|p=≥}}

| period = {{val|308.9|2.3|2.8}}

| semimajor = {{val|0.882|0.035|0.039}}

| eccentricity = {{val|0.742|0.017|0.018}}

}}

{{OrbitboxPlanet

| exoplanet = c

| mass = {{val|7.868|1.760|1.599}}

| period = {{val|9296.0|4133.0|2422.1}}

| semimajor = {{val|8.540|2.334|1.584}}

| eccentricity = {{val|0.149|0.112|0.087}}

| inclination = {{val|11.420|5.388|3.070}}

}}

{{Orbitbox end}}

See also

References

{{Reflist|refs=

{{cite simbad

| title=HD 43197 | access-date=2021-10-20 }}

{{Cite Gaia DR3|2896745747966986240}}

{{cite XHIP|29550}}

{{cite book

| title=Michigan catalogue of two-dimensional spectral types for the HD stars

| last=Houk | first=Nancy

| volume=3 | date=1982

| location=Ann Arbor, Michigan

| publisher=Dept. of Astronomy, University of Michigan

| bibcode=1982mcts.book.....H }}

{{cite journal

| title=Revising the ages of planet-hosting stars

| last1=Bonfanti | first1=A. | last2=Ortolani | first2=S.

| last3=Piotto | first3=G. | last4=Nascimbeni | first4=V.

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

| year=2015 | volume=575 | at=A18

| arxiv=1411.4302 | bibcode=2015A&A...575A..18B

| doi=10.1051/0004-6361/201424951 | s2cid=54555839 }}

{{cite journal

| title=The HARPS Search for Southern Extrasolar Planets XXIII. 8 Planetary Companions to Low-activity Solar-type Stars

| last1=Naef | first1=Dominique | last2=Mayor | first2=Michel

| last3=Lo Curto | first3=Gaspare | last4=Bouchy | first4=François

| last5=Lovis | first5=Christophe | last6=Moutou | first6=Claire

| last7=Benz | first7=Willy | last8=Pepe | first8=Francesco

| last9=Queloz | first9=Didier | last10=Santos | first10=Nuno C.

| last11=Ségransan | first11=Damien | last12=Udry | first12=Stéphane

| last13=Bonfils | first13=Xavier | last14=Delfosse | first14=Xavier

| last15=Forveille | first15=Thierry | last16=Hébrard | first16=Guillaume

| last17=Mordasini | first17=Christoph | last18=Perrier | first18=Christian

| last19=Boisse | first19=Isabelle | last20=Sosnowska | first20=Danuta

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

| volume=523 | page=A15 | year=2010

| arxiv=1008.4600 | bibcode=2010A&A...523A..15N

| doi=10.1051/0004-6361/200913616 | s2cid=118845989 }}

{{cite journal

| title=Detectability of Exoplanet Periastron Passage in the Infrared

| last1=Kane | first1=Stephen R. | last2=Gelino | first2=Dawn M.

| journal=The Astrophysical Journal

| volume=741 | issue=1 | id=52 | pages=9 | date=November 2011

| doi=10.1088/0004-637X/741/1/52 | arxiv=1108.1803

| bibcode=2011ApJ...741...52K | s2cid=42643810 }}

{{Cite web

| url=https://www.nameexoworlds.iau.org/final-results

| title=Approved names | website=NameExoworlds | publisher=IAU

| language=en | access-date=2020-01-02 }}

{{Cite web

| url=https://www.iau.org/news/pressreleases/detail/iau1912/|title=International Astronomical Union {{!}} IAU

| website=www.iau.org | publisher=IAU | access-date=2020-01-02 }}

{{cite journal |last1=Feng |first1=Fabo |last2=Butler |first2=R. Paul |display-authors=etal |date=August 2022 |title=3D Selection of 167 Substellar Companions to Nearby Stars |journal=The Astrophysical Journal Supplement Series |volume=262 |issue=21 |page=21 |doi=10.3847/1538-4365/ac7e57 |arxiv=2208.12720 |bibcode=2022ApJS..262...21F|s2cid=251864022 |doi-access=free }}

}}

{{Sky|06|13|35.6615|-|29|53|50.169|179.2}}

{{Stars of Canis Major}}

{{Authority control}}

{{DEFAULTSORT:HD 43197}}

Category:G-type main-sequence stars

Category:G-type subgiants

Category:Planetary systems with one confirmed planet

Category:Canis Major

Category:Durchmusterung objects

043197

029550

Amadioha