The star
The star
2MASS J01225093-2439505
- Type
- M3.5 V
- Surface
- ≈ 3,530 K
- Size
- 0.37 × the Sun
- Mass
- 0.40 × the Sun
- Brightness
- 0.0191 × the Sun
- Habitable zone
- 0.113–0.292 AU
The planets
2MASS J01225093-2439505
2MASS J01225093-2439505 b
- Year
- 592.9 years
- Distance from star
- 52 AU
- Mass
- 25 Jupiters
- Size
- 11 × Earth
- Temperature
- ≈ 1600 K (+1327 °C)
- Found
- 2013, imaging (W. M. Keck Observatory)
Masses found by the wobble method are minimums, because the orbit's tilt is unknown. Temperatures are equilibrium estimates for a bare planet, before any atmosphere.
How we know
A direct picture
The star's glare is blocked or subtracted, leaving the planet's own faint light as a dot that moves along its orbit over the years.
Sources
- Planet and star parameters: NASA Exoplanet Archive, Planetary Systems Composite Parameters, retrieved 1 Nov 2026. This research has made use of the NASA Exoplanet Archive, which is operated by the California Institute of Technology, under contract with NASA under the Exoplanet Exploration Program.
- Position: HYG Database v4.1 (CC BY-SA 4.0).
- Habitable zone: a simple estimate from the star's brightness (√L × 0.95 to 1.67 AU), shown as a guide.