HD 108236 b
HD 108236 b is a super-Earth orbiting HD 108236 in the constellation Centaurus. It lies about 211 light-years from Earth and was discovered in 2020 using the transit method.
How Big Is HD 108236 b?
HD 108236 b has a radius of 1.62 times that of Earth.
Is HD 108236 b in the Habitable Zone?
HD 108236 b orbits inside the inner edge of the habitable zone of HD 108236. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of HD 108236: 0.636–1.503 AU (conservative: 0.805–1.425 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 HD 108236 b — one full orbit around HD 108236 — lasts 3.80 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.045 AU — closer to its star than Mercury is to the Sun. Its orbit is nearly circular (eccentricity 0.045).
How Was HD 108236 b Discovered?
HD 108236 b was discovered in 2020 using the transit method, with observations from Transiting Exoplanet Survey Satellite (TESS).
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 HD 108236 b?
HD 108236 b is 210.7 light-years (64.6 parsecs) from Earth. Light arriving here tonight left the planet around the year 1816. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 3,708,320 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. HD 108236 b scores 0.28, ranking #2,339 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: HD 108236
HD 108236
- Surface temperature
- 5,660 K (Sun: 5,772 K)
- Mass
- 0.87 M☉
- Radius
- 0.88 R☉
- Luminosity
- 0.7080 L☉
- Age
- 6.7 billion years (Sun: 4.6)
The HD 108236 Planetary System
HD 108236 b is one of 5 known planets in the HD 108236 system. Its siblings:
- HD 108236 c (Mini Neptune)
- HD 108236 e (Sub Neptune)
- HD 108236 f (Mini Neptune)
- TOI-1233.01 (Mini Neptune)
HD 108236 b — Complete Data
| Radius | 1.615 Earth radii (0.144 Jupiter radii) |
|---|---|
| Orbital period | 3.80 days |
| Orbital distance | 0.045 AU |
| Eccentricity | 0.045 |
| Earth Similarity Index | 0.28 |
| Distance from Earth | 210.7 light-years (64.6 parsecs) |
| Constellation | Centaurus |
| Discovery method | Transit |
| Discovery facility | Transiting Exoplanet Survey Satellite (TESS) |
| Discovery year | 2020 |
Data: NASA Exoplanet Archive, last updated 2021-01-21. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About HD 108236 b
Is HD 108236 b habitable?
No — HD 108236 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is HD 108236 b?
HD 108236 b is about 211 light-years from Earth in the constellation Centaurus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 3,708,320 years to get there.
How big is HD 108236 b compared to Earth?
HD 108236 b has 1.62 times the radius of Earth.
How long is a year on HD 108236 b?
One orbit around HD 108236 takes 3.8 Earth days — short enough that 96 of its years would fit into one Earth year.