Kepler-302 b
Kepler-302 b is a Neptune-like planet orbiting Kepler-302 in the constellation Cygnus. It lies about 4,575 light-years from Earth and was discovered in 2014 using the transit method.
How Big Is Kepler-302 b?
Kepler-302 b has a radius of 4.06 times that of Earth.
Is Kepler-302 b in the Habitable Zone?
Kepler-302 b orbits inside the inner edge of the habitable zone of Kepler-302. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of Kepler-302: 0.906–2.136 AU (conservative: 1.147–2.025 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-302 b — one full orbit around Kepler-302 — lasts 30.2 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.193 AU — closer to its star than Mercury is to the Sun.
How Was Kepler-302 b Discovered?
Kepler-302 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-302 b?
Kepler-302 b is 4,574.6 light-years (1,402.6 parsecs) from Earth. Light arriving here tonight left the planet about 4,575 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 80,512,960 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-302 b scores 0.21, ranking #3,744 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: Kepler-302
Kepler-302
- Surface temperature
- 5,740 K (Sun: 5,772 K)
- Radius
- 1.22 R☉
The Kepler-302 Planetary System
Kepler-302 b is one of 2 known planets in the Kepler-302 system. Its siblings:
- Kepler-302 c (Cold Gas Giant)
Kepler-302 b — Complete Data
| Radius | 4.060 Earth radii (0.362 Jupiter radii) |
|---|---|
| Orbital period | 30.18 days |
| Orbital distance | 0.193 AU |
| Earth Similarity Index | 0.21 |
| Distance from Earth | 4,574.6 light-years (1,402.6 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-302 b
Is Kepler-302 b habitable?
No — Kepler-302 b orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is Kepler-302 b?
Kepler-302 b is about 4,575 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 80,512,960 years to get there.
How big is Kepler-302 b compared to Earth?
Kepler-302 b has 4.06 times the radius of Earth.
How long is a year on Kepler-302 b?
One orbit around Kepler-302 takes 30.2 Earth days — short enough that 12 of its years would fit into one Earth year.
Explore Kepler-302 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.
