Kepler-1985 b
Kepler-1985 b is a mini-Neptune orbiting Kepler-1985 in the constellation Cygnus. It was discovered in 2023 using the transit method.
How Big Is Kepler-1985 b?
Kepler-1985 b has a radius of 2.27 times that of Earth.
Is Kepler-1985 b in the Habitable Zone?
Kepler-1985 b orbits inside the inner edge of the habitable zone of Kepler-1985. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of Kepler-1985: 0.641–1.529 AU (conservative: 0.812–1.450 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 Kepler-1985 b
The equilibrium temperature of Kepler-1985 b is about 1,129 K (856 °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. It receives 383 times the stellar energy that Earth gets from the Sun.
Orbit and Year Length
A year on Kepler-1985 b — one full orbit around Kepler-1985 — lasts 3.42 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.043 AU — closer to its star than Mercury is to the Sun.
How Was Kepler-1985 b Discovered?
Kepler-1985 b was discovered in 2023 using the transit method, with observations from Kepler.
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.
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. Kepler-1985 b scores 0.24, ranking #3,213 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-1985
Kepler-1985
- Surface temperature
- 5,370 K (Sun: 5,772 K)
- Mass
- 0.88 M☉
- Radius
- 0.97 R☉
Planetary System
Kepler-1985 b is the only planet known to orbit Kepler-1985 so far.
Kepler-1985 b — Complete Data
| Radius | 2.270 Earth radii (0.203 Jupiter radii) |
|---|---|
| Orbital period | 3.42 days |
| Orbital distance | 0.043 AU |
| Equilibrium temperature | 1,129 K (856 °C) |
| Stellar irradiation | 382.68× Earth |
| Earth Similarity Index | 0.24 |
| Constellation | Cygnus |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2023 |
Data: NASA Exoplanet Archive, last updated 2017-05-08. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-1985 b
Is Kepler-1985 b habitable?
No — Kepler-1985 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How big is Kepler-1985 b compared to Earth?
Kepler-1985 b has 2.27 times the radius of Earth.
How long is a year on Kepler-1985 b?
One orbit around Kepler-1985 takes 3.4 Earth days — short enough that 107 of its years would fit into one Earth year.
Explore Kepler-1985 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.
