The star
The star
Kepler-444
- Type
- K
- Surface
- ≈ 5,046 K
- Size
- 0.75 × the Sun
- Mass
- 0.76 × the Sun
- Brightness
- 0.376 × the Sun
- Habitable zone
- 0.479–1.16 AU
The planets
Kepler-444
Kepler-444 b
- Year
- 3.60 days
- Distance from star
- 0.0418 AU
- Mass
- 0.037 Earths
- Size
- 0.4 × Earth
- Temperature
- ≈ 938 K (+665 °C)
- Found
- 2015, transit (Kepler)
Kepler-444
Kepler-444 c
- Year
- 4.55 days
- Distance from star
- 0.0488 AU
- Mass
- 0.079 Earths
- Size
- 0.5 × Earth
- Temperature
- ≈ 868 K (+595 °C)
- Found
- 2015, transit (Kepler)
Kepler-444
Kepler-444 d
- Year
- 6.19 days
- Distance from star
- 0.06 AU
- Mass
- 0.2 Earths
- Size
- 0.53 × Earth
- Temperature
- ≈ 783 K (+510 °C)
- Found
- 2015, transit (Kepler)
Kepler-444
Kepler-444 e
- Year
- 7.74 days
- Distance from star
- 0.0696 AU
- Mass
- 0.1 Earths
- Size
- 0.55 × Earth
- Temperature
- ≈ 727 K (+454 °C)
- Found
- 2015, transit (Kepler)
Kepler-444
Kepler-444 f
- Year
- 9.74 days
- Distance from star
- 0.0811 AU
- Mass
- 0.33 Earths
- Size
- 0.74 × Earth
- Temperature
- ≈ 673 K (+400 °C)
- Found
- 2015, transit (Kepler)
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
The shadow
The planet passes in front of its star and dims it by a fraction of a percent, every orbit. The dip gives the planet's size and year.
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.