WASP-42#Planetary system

{{Short description|Star in the constellation Centaurus}}

{{Starbox begin}}

{{Starbox observe

| epoch = J2000

| constell = Centaurus

| ra = {{RA|12|51|55.5580}}

| dec = {{DEC|-42|04|25.095}}

| appmag_v = 12.6{{citation|arxiv=1512.05549|title=High-precision photometry by telescope defocussing. III. WASP-22, WASP-41, WASP-42 and WASP-55|year=2015|doi=10.1093/mnras/stw279|last1=Southworth|first1=John|last2=Tregloan-Reed|first2=J.|last3=Andersen|first3=M. I.|last4=Calchi Novati|first4=S.|last5=Ciceri|first5=S.|last6=Colque|first6=J. P.|last7=D'Ago|first7=G.|last8=Dominik|first8=M.|last9=Evans|first9=D.|last10=Gu|first10=S. -H.|last11=Herrera-Cruces|first11=A.|last12=Hinse|first12=T. C.|last13=Jorgensen|first13=U. G.|last14=Juncher|first14=D.|last15=Kuffmeier|first15=M.|last16=Mancini|first16=L.|last17=Peixinho|first17=N.|last18=Popovas|first18=A.|last19=Rabus|first19=M.|last20=Skottfelt|first20=J.|last21=Tronsgaard|first21=R.|last22=Unda-Sanzana|first22=E.|last23=Wang|first23=X. -B.|last24=Wertz|first24=O.|last25=Alsubai|first25=K. A.|last26=Andersen|first26=J. M.|last27=Bozza|first27=V.|last28=Bramich|first28=D. M.|last29=Burgdorf|first29=M.|last30=Damerdji|first30=Y.|doi-access=free |s2cid=44864064|display-authors=29}}

}}

{{Starbox character

| type = main-sequence star

| class = K1V

}}

{{Starbox astrometry

| radial_v = 41.25{{cite Gaia EDR3|6139698733664726784}}

| prop_mo_ra = −49.875

| prop_mo_dec = 4.963

| parallax = 5.6209

| p_error = 0.0153

| parallax_footnote =

}}

{{Starbox detail

| source =

| mass = 0.881{{±|0.086|0.081}}

| radius = 0.850{{±|0.035}}

| temperature = 5315{{±|79}}

| luminosity =

| gravity = 4.50{{±|0.18}}{{citation|arxiv=1309.1998|title=New and updated stellar parameters for 90 transit hosts The effect of the surface gravity|year=2013|doi=10.1051/0004-6361/201322240|last1=Mortier|first1=A.|last2=Santos|first2=N. C.|last3=Sousa|first3=S. G.|last4=Fernandes|first4=J. M.|last5=Adibekyan|first5=V. Zh.|last6=Delgado Mena|first6=E.|last7=Montalto|first7=M.|last8=Israelian|first8=G.|journal=Astronomy and Astrophysics|volume=558|pages=A106|bibcode=2013A&A...558A.106M|s2cid=118750676}}

| metal_fe = 0.05{{±|0.13}}

| rotation =

| rotational_velocity = 2.70{{±|0.40}}

| age_gyr = 11.3{{±|1.5|4.8}}

}}

{{Starbox catalog

| names = {{odlist|2MASS = J12515557-4204249}}{{cite simbad|title=WASP-42|access-date=2020-12-22}}

}}

{{Starbox reference

| Simbad = WASP-42

}}

{{Starbox end}}

WASP-42 is a K-type main-sequence star. Its surface temperature is 5315{{±|79}} K.{{cite book|last=Southworth|first=J.|date=2016|chapter=4. Physical Properties|title=High-precision photometry by telescope defocussing|url=https://academic.oup.com/mnras/article-pdf/457/4/4205/18755584/stw279.pdf|doi=10.1093/mnras/stw279|volume=VIII. WASP-22, WASP-41, WASP-41 and WASP-55|pages=4210|doi-access=free |access-date=25 October 2023}} WASP-42 is similar to the Sun in concentration of heavy elements, with metallicity ([Fe/H]) of 0.05{{±|0.13}}, and is much older than the Sun at {{val|11.3|1.5|4.8}} billion years. The star does exhibit starspot activity as is typical for its spectral class.

Multiplicity surveys did not detect any stellar companions to WASP-42 in 2017.{{citation|arxiv=1709.07476|title=High-resolution Imaging of Transiting Extrasolar Planetary systems (HITEP). II. Lucky Imaging results from 2015 and 2016|year=2018|doi=10.1051/0004-6361/201731855|last1=Evans|first1=D. F.|last2=Southworth|first2=J.|last3=Smalley|first3=B.|last4=Jørgensen|first4=U. G.|last5=Dominik|first5=M.|last6=Andersen|first6=M. I.|last7=Bozza|first7=V.|last8=Bramich|first8=D. M.|last9=Burgdorf|first9=M. J.|last10=Ciceri|first10=S.|last11=d'Ago|first11=G.|last12=Figuera Jaimes|first12=R.|last13=Gu|first13=S.-H.|last14=Hinse|first14=T. C.|last15=Henning|first15=Th.|last16=Hundertmark|first16=M.|last17=Kains|first17=N.|last18=Kerins|first18=E.|last19=Korhonen|first19=H.|last20=Kokotanekova|first20=R.|last21=Kuffmeier|first21=M.|last22=Longa-Peña|first22=P.|last23=Mancini|first23=L.|last24=MacKenzie|first24=J.|last25=Popovas|first25=A.|last26=Rabus|first26=M.|last27=Rahvar|first27=S.|last28=Sajadian|first28=S.|last29=Snodgrass|first29=C.|last30=Skottfelt|first30=J.|journal=Astronomy & Astrophysics|volume=610|pages=A20|bibcode=2018A&A...610A..20E|s2cid=53400492|display-authors=29}}