K2-167 b
K2-167 b is a mini-Neptune orbiting K2-167 in the constellation Aquarius. It lies about 264 light-years from Earth and was discovered in 2018 using the transit method.
How Big Is K2-167 b?
K2-167 b has a radius of 2.37 times that of Earth.
Is K2-167 b in the Habitable Zone?
K2-167 b orbits inside the inner edge of the habitable zone of K2-167. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of K2-167: 1.302–3.031 AU (conservative: 1.649–2.874 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 K2-167 b
The equilibrium temperature of K2-167 b is about 1,220 K (947 °C) — hot enough to melt many metals. This estimate ignores any atmosphere, which could change surface temperatures dramatically — Earth's greenhouse effect adds about 33 °C.
Orbit and Year Length
A year on K2-167 b — one full orbit around K2-167 — lasts 9.98 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.093 AU — closer to its star than Mercury is to the Sun. Its orbit is highly elliptical (eccentricity 0.48), swinging dramatically closer to and farther from its star.
How Was K2-167 b Discovered?
K2-167 b was discovered in 2018 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 K2-167 b?
K2-167 b is 263.9 light-years (80.9 parsecs) from Earth. Light arriving here tonight left the planet around the year 1763. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 4,644,640 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. K2-167 b scores 0.24, ranking #3,240 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: K2-167
K2-167
- Surface temperature
- 6,310 K (Sun: 5,772 K)
- Mass
- 1.08 M☉
- Radius
- 1.50 R☉
- Luminosity
- 3.2100 L☉
- Age
- 5.3 billion years (Sun: 4.6)
Planetary System
K2-167 b is the only planet known to orbit K2-167 so far.
K2-167 b — Complete Data
| Radius | 2.365 Earth radii (0.211 Jupiter radii) |
|---|---|
| Orbital period | 9.98 days |
| Orbital distance | 0.093 AU |
| Eccentricity | 0.480 |
| Equilibrium temperature | 1,220 K (947 °C) |
| Earth Similarity Index | 0.24 |
| Distance from Earth | 263.9 light-years (80.9 parsecs) |
| Constellation | Aquarius |
| Discovery method | Transit |
| Discovery facility | K2 |
| Discovery year | 2018 |
Data: NASA Exoplanet Archive, last updated 2024-11-20. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About K2-167 b
Is K2-167 b habitable?
No — K2-167 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is K2-167 b?
K2-167 b is about 264 light-years from Earth in the constellation Aquarius. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 4,644,640 years to get there.
How big is K2-167 b compared to Earth?
K2-167 b has 2.37 times the radius of Earth.
How long is a year on K2-167 b?
One orbit around K2-167 takes 10.0 Earth days — short enough that 37 of its years would fit into one Earth year.