The star
The star
K2-72
- Type
- red dwarf
- Surface
- ≈ 3,360 K
- Size
- 0.33 × the Sun
- Mass
- 0.27 × the Sun
- Brightness
- 0.0146 × the Sun
- Habitable zone
- 0.0989–0.258 AU
The planets
K2-72
K2-72 b
- Year
- 5.58 days
- Distance from star
- 0.04 AU
- Mass
- 1.3 Earths
- Size
- 1.1 × Earth
- Temperature
- ≈ 466 K (+193 °C)
- Found
- 2016, transit (K2)
K2-72
K2-72 d
- Year
- 7.76 days
- Distance from star
- 0.05 AU
- Mass
- 1 Earths
- Size
- 1 × Earth
- Temperature
- ≈ 417 K (+144 °C)
- Found
- 2016, transit (K2)
K2-72
K2-72 c
- Year
- 15.19 days
- Distance from star
- 0.078 AU
- Mass
- 1.6 Earths
- Size
- 1.2 × Earth
- Temperature
- ≈ 334 K (+61 °C)
- Found
- 2016, transit (K2)
K2-72
K2-72 e
- Year
- 24.16 days
- Distance from star
- 0.106 AU
- Mass
- 2.2 Earths
- Size
- 1.3 × Earth
- Temperature
- ≈ 286 K (+13 °C)
- Found
- 2016, 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.