KOI-351 d
KOI-351 d is a mini-Neptune orbiting KOI-351 in the constellation Draco. It lies about 2,767 light-years from Earth and was discovered in 2013 using the transit method.
How Big Is KOI-351 d?
KOI-351 d has a radius of 2.87 times that of Earth.
Is KOI-351 d in the Habitable Zone?
KOI-351 d orbits inside the inner edge of the habitable zone of KOI-351. So close to its star, surface conditions are far too hot for liquid water.
Habitable zone of KOI-351: 1.034–2.422 AU (conservative: 1.310–2.297 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 KOI-351 d — one full orbit around KOI-351 — lasts 59.7 Earth days, shorter than Mercury's 88-day year. It orbits at an average distance of 0.320 AU — closer to its star than Mercury is to the Sun.
How Was KOI-351 d Discovered?
KOI-351 d was discovered in 2013 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 KOI-351 d?
KOI-351 d is 2,766.6 light-years (848.3 parsecs) from Earth. Light arriving here tonight left the planet about 2,767 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 48,692,160 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. KOI-351 d scores 0.28, ranking #2,234 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.
The Host Star: KOI-351
KOI-351
- Surface temperature
- 6,015 K (Sun: 5,772 K)
- Mass
- 1.12 M☉
- Radius
- 1.29 R☉
The KOI-351 Planetary System
KOI-351 d is one of 8 known planets in the KOI-351 system. Its siblings:
KOI-351 d — Complete Data
| Radius | 2.870 Earth radii (0.256 Jupiter radii) |
|---|---|
| Orbital period | 59.74 days |
| Orbital distance | 0.320 AU |
| Earth Similarity Index | 0.28 |
| Distance from Earth | 2,766.6 light-years (848.3 parsecs) |
| Constellation | Draco |
| Discovery method | Transit |
| Discovery facility | Kepler |
| Discovery year | 2013 |
Data: NASA Exoplanet Archive, last updated 2014-05-14. Earth Similarity Index: PHL @ UPR Arecibo.
Frequently Asked Questions About KOI-351 d
Is KOI-351 d habitable?
No — KOI-351 d orbits too close to its star and is too hot for liquid water to exist on its surface.
How far away is KOI-351 d?
KOI-351 d is about 2,767 light-years from Earth in the constellation Draco. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 48,692,160 years to get there.
How big is KOI-351 d compared to Earth?
KOI-351 d has 2.87 times the radius of Earth.
How long is a year on KOI-351 d?
One orbit around KOI-351 takes 59.7 Earth days.
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