HAT-P-9 b
A confirmed exoplanet orbiting HAT-P-9.
Compared with Earth
- Size
- About 16 times Earth's width.
- Mass
- About 238 times Earth's mass.
- Temperature
- About 1,267 °C (2,312 °F) from starlight alone, against -18 °C (-1 °F) for Earth measured the same way.
- Starlight
- About 931 times the starlight Earth gets from the Sun.
- Year
- A year here lasts about 3.9 Earth days.
Planet
- Radius
- 15.61 × Earth
- Mass
- 238.1 × Earth
- Density
- 0.342 g/cm³
- Equilibrium temperature
- 1,540 K
- Starlight received
- 931 × Earth
- Orbital period
- 3.923 days
- Average distance from its star
- 0.05287 AU
Star
- Host star
- HAT-P-9
- Spectral class
- F — yellow-white
- Surface temperature
- 6,350 K
- Radius
- 1.338 × Sun
- Mass
- 1.281 × Sun
- Age
- Unknown
System
- Distance from Earth
- 1,485 light-years (455.2 parsecs)
- Stars in system
- 1
- Known planets
- 1
Discovery
- Year
- 2008
- Method
- Transit
- Facility
- HATNet
Data from the NASA Exoplanet Archive, synced October 14, 2026.