The star
The star
K2-43
- Type
- red dwarf
- Surface
- ≈ 3,841 K
- Size
- 0.54 × the Sun
- Mass
- 0.57 × the Sun
- Brightness
- 0.0613 × the Sun
- Habitable zone
- 0.201–0.514 AU
The planets
K2-43
K2-43 b
- Year
- 3.47 days
- Distance from star
- 0.0378 AU
- Mass
- 18 Earths
- Size
- 4.5 × Earth
- Temperature
- ≈ 939 K (+666 °C)
- Found
- 2016, transit (K2)
K2-43
K2-43 c
- Year
- 2.20 days
- Distance from star
- 0.0274 AU
- Mass
- 6.4 Earths
- Size
- 2.4 × Earth
- Temperature
- ≈ 1094 K (+821 °C)
- Found
- 2019, transit (K2)
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.