Kepler-389 b
Kepler-389 b is a super-Earth orbiting Kepler-389 in the constellation Cygnus. It lies about 2,663 light-years from Earth and was discovered in 2014 using the transit method.
How Big Is Kepler-389 b?
Kepler-389 b has a radius of 1.51 times that of Earth.
Is Kepler-389 b in the Habitable Zone?
Kepler-389 b orbits inside the inner edge of the habitable zone of Kepler-389. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of Kepler-389: 0.527–1.256 AU (conservative: 0.667–1.191 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 Kepler-389 b — one full orbit around Kepler-389 — lasts 3.24 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.041 AU — closer to its star than Mercury is to the Sun.
How Was Kepler-389 b Discovered?
Kepler-389 b was discovered in 2014 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.
How Far Away Is Kepler-389 b?
Kepler-389 b is 2,663.3 light-years (816.6 parsecs) from Earth. Light arriving here tonight left the planet about 2,663 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 46,874,080 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. Kepler-389 b scores 0.29, ranking #2,032 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-389
Kepler-389
- Surface temperature
- 5,376 K (Sun: 5,772 K)
- Radius
- 0.79 R☉
The Kepler-389 Planetary System
Kepler-389 b is one of 2 known planets in the Kepler-389 system. Its siblings:
- Kepler-389 c (Super Earth)
Kepler-389 b — Complete Data
| Radius | 1.510 Earth radii (0.135 Jupiter radii) |
|---|---|
| Orbital period | 3.24 days |
| Orbital distance | 0.041 AU |
| Earth Similarity Index | 0.29 |
| Distance from Earth | 2,663.3 light-years (816.6 parsecs) |
| Constellation | Cygnus |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2014 |
Data: NASA Exoplanet Archive, last updated 2014-05-14. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About Kepler-389 b
Is Kepler-389 b habitable?
No — Kepler-389 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is Kepler-389 b?
Kepler-389 b is about 2,663 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 46,874,080 years to get there.
How big is Kepler-389 b compared to Earth?
Kepler-389 b has 1.51 times the radius of Earth.
How long is a year on Kepler-389 b?
One orbit around Kepler-389 takes 3.2 Earth days — short enough that 113 of its years would fit into one Earth year.
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