K2-116 b
K2-116 b is a terrestrial planet orbiting K2-116 in the constellation Aquarius. It lies about 161 light-years from Earth and was discovered in 2017 using the transit method.
How Big Is K2-116 b?
K2-116 b has a radius of 0.69 times that of Earth.
Is K2-116 b in the Habitable Zone?
K2-116 b orbits inside the inner edge of the habitable zone of K2-116. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of K2-116: 0.305–0.758 AU (conservative: 0.386–0.719 AU), per Kopparapu et al. (2014). Earth orbits the Sun at 1 AU.
See the full interactive habitable-zone view in the Exoplanet Explorer app ›
Temperature on K2-116 b
K2-116 b receives 78.60 times the stellar energy that Earth gets from the Sun.
Orbit and Year Length
A year on K2-116 b — one full orbit around K2-116 — lasts 4.66 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.048 AU — closer to its star than Mercury is to the Sun. Its orbit is mildly elliptical (eccentricity 0.06).
How Was K2-116 b Discovered?
K2-116 b was discovered in 2017 using the transit method, with observations from K2.
The transit method watches a star for the tiny, regular dip in brightness that occurs when a planet crosses in front of it. The depth and timing of these dips reveal the planet's size and orbital period.
How Far Away Is K2-116 b?
K2-116 b is 161.1 light-years (49.4 parsecs) from Earth. Light arriving here tonight left the planet around the year 1865. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 2,835,360 years to make the journey.
Earth Similarity Index
The Earth Similarity Index (ESI) scores how physically similar a planet is to Earth, from 0 to 1, based on radius, density, escape velocity and surface temperature. K2-116 b scores 0.30, ranking #1,408 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: K2-116
K2-116
- Surface temperature
- 4,348 K (Sun: 5,772 K)
- Mass
- 0.69 M☉
- Radius
- 0.67 R☉
Planetary System
K2-116 b is the only planet known to orbit K2-116 so far.
K2-116 b — Complete Data
| Radius | 0.690 Earth radii (0.062 Jupiter radii) |
|---|---|
| Orbital period | 4.66 days |
| Orbital distance | 0.048 AU |
| Eccentricity | 0.060 |
| Stellar irradiation | 78.60× Earth |
| Earth Similarity Index | 0.30 |
| Distance from Earth | 161.1 light-years (49.4 parsecs) |
| Constellation | Aquarius |
| Discovery method | Transit |
| Discovery facility | K2 |
| Discovery year | 2017 |
Data: NASA Exoplanet Archive, last updated 2017-10-03. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About K2-116 b
Is K2-116 b habitable?
No — K2-116 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is K2-116 b?
K2-116 b is about 161 light-years from Earth in the constellation Aquarius. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 2,835,360 years to get there.
How big is K2-116 b compared to Earth?
K2-116 b has 0.69 times the radius of Earth.
How long is a year on K2-116 b?
One orbit around K2-116 takes 4.7 Earth days — short enough that 78 of its years would fit into one Earth year.
Explore K2-116 b in the app
Browse, filter and compare 6,000+ exoplanets on iPhone, iPad and Apple Watch — with habitable-zone views, widgets and offline data.
