HAT-P-13b

{{Short description|Hot Jupiter orbiting HAT-P-13}}

{{Infobox planet

| name = HAT-P-13b

| image = Exoplanet Comparison HAT-P-13 b.png

| caption = Size comparison of HAT-P-13b with Jupiter.

| discoverer = Bakos et al.

| discovery_site = {{flag|United States}}

| discovered = 21 July 2009

| discovery_method = Transit
Radial velocity

| apsis = astron

| semimajor = {{convert|0.0426|AU|km|abbr=on}}

| eccentricity = 0.021

| period = 2.91626 d

| inclination = 83.4

| arg_peri = 181

| star = HAT-P-13

| mean_radius = 1.28 {{Jupiter radius|link=y}}

| mass = 0.851 {{Jupiter mass|link=y}}

}}

HAT-P-13b is an extrasolar planet approximately 700 light-years away in the constellation Ursa Major. The planet was discovered when it transited across its sun, HAT-P-13. This planet is a hot Jupiter with 0.851 times the mass of Jupiter and 1.28 radius. The planet has a lower mass, but its overall size is larger than Jupiter.

The study in 2012, utilizing a Rossiter–McLaughlin effect, have determined the planetary orbit is probably aligned with the rotational axis of the star, misalignment equal to 1.9{{±|8.6}}°.{{citation|arxiv=1206.6105|title=Obliquities of Hot Jupiter Host Stars: Evidence for Tidal Interactions and Primordial Misalignments|year=2012|doi=10.1088/0004-637X/757/1/18|last1=Albrecht|first1=Simon|last2=Winn|first2=Joshua N.|last3=Johnson|first3=John A.|last4=Howard|first4=Andrew W.|last5=Marcy|first5=Geoffrey W.|last6=Butler|first6=R. Paul|last7=Arriagada|first7=Pamela|last8=Crane|first8=Jeffrey D.|last9=Shectman|first9=Stephen A.|last10=Thompson|first10=Ian B.|last11=Hirano|first11=Teruyuki|last12=Bakos|first12=Gaspar|last13=Hartman|first13=Joel D.|journal=The Astrophysical Journal|volume=757|issue=1|page=18|bibcode=2012ApJ...757...18A|s2cid=17174530}}