K2-156 b
K2-156 b is a terrestrial planet orbiting K2-156 in the constellation Virgo. It lies about 490 light-years from Earth and was discovered in 2018 using the transit method.
How Big Is K2-156 b?
K2-156 b has a radius of 1.10 times that of Earth.
Is K2-156 b in the Habitable Zone?
The position of K2-156 b relative to the habitable zone of K2-156 cannot be precisely determined from the available orbital data.
Habitable zone of K2-156: 0.296–0.732 AU (conservative: 0.375–0.694 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 ›
Orbit and Year Length
A year on K2-156 b — one full orbit around K2-156 — lasts just 19.5 hours, shorter than Mercury's 88-day year.
How Was K2-156 b Discovered?
K2-156 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 K2-156 b?
K2-156 b is 489.9 light-years (150.2 parsecs) from Earth. Light arriving here tonight left the planet around the year 1537. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 8,622,240 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. K2-156 b scores 0.29, ranking #1,598 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: K2-156
K2-156
- Surface temperature
- 4,460 K (Sun: 5,772 K)
- Radius
- 0.62 R☉
Planetary System
K2-156 b is the only planet known to orbit K2-156 so far.
K2-156 b — Complete Data
| Radius | 1.100 Earth radii (0.098 Jupiter radii) |
|---|---|
| Orbital period | 0.81 days |
| Earth Similarity Index | 0.29 |
| Distance from Earth | 489.9 light-years (150.2 parsecs) |
| Constellation | Virgo |
| Discovery method | Transit |
| Discovery facility | K2 |
| Discovery year | 2018 |
Data: NASA Exoplanet Archive, last updated 2022-03-28. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About K2-156 b
Is K2-156 b habitable?
K2-156 b is not known to orbit within the habitable zone of K2-156, and as a terrestrial planet it is an unlikely candidate for life as we know it.
How far away is K2-156 b?
K2-156 b is about 490 light-years from Earth in the constellation Virgo. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 8,622,240 years to get there.
How big is K2-156 b compared to Earth?
K2-156 b has 1.10 times the radius of Earth.
How long is a year on K2-156 b?
One orbit around K2-156 takes 0.8 Earth days — short enough that 449 of its years would fit into one Earth year.
Explore K2-156 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.
