 WASP @-@ 13b is a transiting planet with an estimated mass that is ( including limb darkening ) 0 @.@ 477 times that of Jupiter and a radius that is 1 @.@ 389 times Jupiter 's radius . The planet is , in other words , less than half the mass of Jupiter , but slightly less than fourteen tenths its size . WASP @-@ 13b 's low mass can mostly likely be attributed to the presence of a low @-@ mass core , or to the total lack of a core , according to the discovery paper . WASP @-@ 13b , which orbits its host star at a distance of 0 @.@ 05362 AU , circles its star completely every 4 @.@ 35298 days . The 2011 study on the planet recognized WASP @-@ 13b as the fifth lowest @-@ density extrasolar planet known , behind Kepler @-@ 7b ; WASP @-@ 17b ; TrES @-@ 4b ; and COROT @-@ 5b . 
 WASP @-@ 13b <a href='drop_aux' title='1'><mark>is</mark></a>a transiting planet with an estimated mass <a href='null_relcl' title='2'><mark>that</mark></a>is ( including limb darkening ) 0 @.@ 477 times that of Jupiter and a radius <a href='null_relcl' title='3'><mark>that</mark></a><a href='drop_aux' title='4'><mark>is</mark></a>1 @.@ 389 times Jupiter <a href='null_genetive' title='5'><mark>'s</mark></a>radius . The planet <a href='drop_aux' title='6'><mark>is</mark></a>, in other words , less than half the mass of Jupiter , but slightly less than fourteen tenths its size . WASP @-@ 13b <a href='null_genetive' title='7'><mark>'s</mark></a>low mass can mostly likely be attributed to the presence of a low @-@ mass core , or to the total lack of a core , according to the discovery paper . WASP @-@ 13b , which <a href='uninflect' title='8'><mark>orbits</mark></a> its host star at a distance of 0 @.@ 05362 AU , <a href='uninflect' title='9'><mark>circles</mark></a> its star completely every 4 @.@ 35298 days . The 2011 study on the planet recognized WASP @-@ 13b as the fifth lowest @-@ density extrasolar planet known , behind Kepler @-@ 7b ; WASP @-@ 17b ; TrES @-@ 4b ; and COROT @-@ 5b . 
WASP @-@ 13b a transiting planet with an estimated mass is ( including limb darkening ) 0 @.@ 477 times that of Jupiter and a radius 1 @.@ 389 times Jupiter  radius . da planet , in other words , less than half the mass of Jupiter , but slightly less than fourteen tenths its size . WASP @-@ 13b  low mass can mostly likely be attributed to the presence of a low @-@ mass core , or to tdatotal lack of a core , according to the discovery paper . WASP @-@ 13b , which orbit its host star at a distance of 0 @.@ 05362 AU , circle its star completely every 4 @.@ 35298 dayz . Thda011 study on the planet recognized WASP @-@ 13b as the fifth lowest @-@ density extrasolar planet known , behind Kepler @-@ 7b ; WASP @-@ 17b ; TrES @-@ 4b ; and COROT @-@ 5b .