HD 149026 b

HD 149026 b / Smertrios
Size comparison of Smertrios with Neptune and Jupiter.
Discovery
Discovered byB. Sato,
D. Fischer,
G. Henry et al.[1]
Discovery siteW. M. Keck Observatory
Discovery date1 July 2005
Radial velocity
Orbital characteristics
0.042 AU (6.3 Gm)
Eccentricity0
2.87588874 ± 5.9×10−7[2] d
Semi-amplitude43.2 ± 2.6
StarOgma
Physical characteristics
0.725 ± 0.03 RJ
Mass0.36 ± 0.03 MJ
Mean density
1.252 g/cm3
Temperature2,300 K (2,030 °C; 3,680 °F)

HD 149026 b, formally named Smertrios /ˈsmɜːrtriɒs/, is an extrasolar planet and hot Jupiter approximately 250 light-years from the Sun in the constellation of Hercules.

The 2.8766-day period planet orbits the yellow subgiant star HD 149026 at a distance of 0.042 AU (3.9 million mi; 6.3 million km) and is notable first as a transiting planet, and second for a small measured radius (relative to mass and incoming heat) that suggests an exceptionally large planetary core.

  1. ^ Cite error: The named reference Sato2005 was invoked but never defined (see the help page).
  2. ^ Cite error: The named reference Zhang2018 was invoked but never defined (see the help page).