WASP-2b

{{Short description|Extrasolar planet in the constellation Delphinus}}

{{Infobox planet

| name = WASP-2b

| image = Exoplanet Comparison WASP-2 b.png

| caption = Size comparison of WASP-2b with Jupiter.

| discoverer = Cameron et al. (SuperWASP)

| discovery_site = SAAO

| discovered = September 25, 2006

| discovery_method = Transit

| apsis = astron

| semimajor = 0.03138 (± 0.011) AU

| eccentricity = 0

| period = 2.15222144 (± 4e-07) d

| inclination = 84.73 (± 0.19)

| star = WASP-2 A

| mean_radius = 1.079 ± 0.033 {{Jupiter radius|link=y}}

| mass = 0.847 ± 0.045 {{Jupiter mass|link=y}}

| surface_grav = 3.279 ± 0.036 g

| single_temperature = 1253 K{{citation|arxiv=2011.07169|title=Multi-color photometry and parameters estimation of Jupiter-sized exoplanets; TRES-3b, WASP-2b and HATP-30b|year=2020|last1=Saeed |first1=M. I. |last2=Goderya |first2=S. N. |last3=Chishtie |first3=F. A. }}

}}

WASP-2b is an extrasolar planet orbiting the star WASP-2 located about 500 light years away in the constellation of Delphinus. It was discovered via the transit method, and then follow up measurements using the radial velocity method confirmed that WASP-2b was a planet. The planet's mass and radius indicate that it is a gas giant with a similar bulk composition to Jupiter. Unlike Jupiter, but similar to many other planets detected around other stars, WASP-2b is located very close to its star, and belongs to the class of planets known as hot Jupiters.{{cite journal

| url=http://www.iop.org/EJ/article/0004-637X/658/2/1322/70612.html

| author= Charbonneau

| title=Precise Radius Estimates for the Exoplanets WASP-1b and WASP-2b

| journal=The Astrophysical Journal

| volume=658

| issue=2

| year=2006

| pages=1322–1327

| doi=10.1086/512008

| last2=Winn

| first2=Joshua N.

| last3=Everett

| first3=Mark E.

| last4=Latham

| first4=David W.

| last5=Holman

| first5=Matthew J.

| last6=Esquerdo

| first6=Gilbert A.

| last7=O’donovan

| first7=Francis T.

| bibcode=2007ApJ...658.1322C|arxiv = astro-ph/0610589 | s2cid= 14099767

}} A 2008 study concluded that the WASP-2b system (among others) is a binary star system allowing even more accurate determination of stellar and planetary parameters.{{cite journal | url=http://www.mpia.de/homes/henning/Publications/daemgen.pdf

| title=Binarity of transit host stars - Implications for planetary parameters

| year=2009

| volume=498 | issue=2

| pages=567–574

| author=Daemgen

| journal=Astronomy and Astrophysics

| doi=10.1051/0004-6361/200810988 | last2=Hormuth | first2=F. | last3=Brandner | first3=W. | last4=Bergfors | first4=C. | last5=Janson | first5=M. | last6=Hippler | first6=S. | last7=Henning | first7=T. | bibcode=2009A&A...498..567D|arxiv = 0902.2179 | s2cid=9893376

}}