Kepler-306 e
Kepler-306 e is a mini-Neptune orbiting Kepler-306 in the constellation Lyra. It lies about 2,530 light-years from Earth and was discovered in 2014 using the transit method.
How Big Is Kepler-306 e?
Kepler-306 e has a radius of 2.27 times that of Earth.
Is Kepler-306 e in the Habitable Zone?
Kepler-306 e orbits inside the inner edge of the habitable zone of Kepler-306. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of Kepler-306: 0.415–1.005 AU (conservative: 0.526–0.953 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-306 e — one full orbit around Kepler-306 — lasts 44.8 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.227 AU — closer to its star than Mercury is to the Sun.
How Was Kepler-306 e Discovered?
Kepler-306 e 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-306 e?
Kepler-306 e is 2,529.9 light-years (775.7 parsecs) from Earth. Light arriving here tonight left the planet about 2,530 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 44,526,240 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. Kepler-306 e scores 0.41, ranking #433 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-306
Kepler-306
- Surface temperature
- 4,954 K (Sun: 5,772 K)
- Radius
- 0.72 R☉
The Kepler-306 Planetary System
Kepler-306 e is one of 4 known planets in the Kepler-306 system. Its siblings:
- Kepler-306 b (Super Earth)
- Kepler-306 c (Mini Neptune)
- Kepler-306 d (Mini Neptune)
Kepler-306 e — Complete Data
| Radius | 2.270 Earth radii (0.203 Jupiter radii) |
|---|---|
| Orbital period | 44.84 days |
| Orbital distance | 0.227 AU |
| Earth Similarity Index | 0.41 |
| Distance from Earth | 2,529.9 light-years (775.7 parsecs) |
| Constellation | Lyra |
| 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-306 e
Is Kepler-306 e habitable?
No — Kepler-306 e orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is Kepler-306 e?
Kepler-306 e is about 2,530 light-years from Earth in the constellation Lyra. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 44,526,240 years to get there.
How big is Kepler-306 e compared to Earth?
Kepler-306 e has 2.27 times the radius of Earth.
How long is a year on Kepler-306 e?
One orbit around Kepler-306 takes 44.8 Earth days.
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