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Kepler-818 b

Neptune-like Cygnus

Kepler-818 b is a Neptune-like planet orbiting Kepler-818 in the constellation Cygnus. It lies about 3,017 light-years from Earth and was discovered in 2016 using the transit method.

5.11×Earth radius
10 dOrbital period
0.16Earth similarity
3,017 lyDistance
2016Discovered

How Big Is Kepler-818 b?

Earth1.00 R⊕Kepler-818 b5.11 R⊕Jupiter11.21 R⊕
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Kepler-818 b has a radius of 5.11 times that of Earth.

Is Kepler-818 b in the Habitable Zone?

The position of Kepler-818 b relative to the habitable zone of Kepler-818 cannot be precisely determined from the available orbital data.

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of Kepler-818: 0.663–1.568 AU (conservative: 0.840–1.486 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-818 b — one full orbit around Kepler-818 — lasts 10.0 Earth days, shorter than Mercury's 88-day year.

How Was Kepler-818 b Discovered?

Kepler-818 b was discovered in 2016 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-818 b?

Kepler-818 b is 3,017.1 light-years (925.0 parsecs) from Earth. Light arriving here tonight left the planet about 3,017 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 53,100,960 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-818 b scores 0.16, ranking #4,147 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: Kepler-818

Kepler-818

Surface temperature
5,638 K (Sun: 5,772 K)
Mass
0.94 M☉
Radius
0.92 R☉
Age
4.0 billion years (Sun: 4.6)

Planetary System

Kepler-818 b is the only planet known to orbit Kepler-818 so far.

Kepler-818 b — Complete Data

Radius5.110 Earth radii (0.456 Jupiter radii)
Orbital period10.04 days
Earth Similarity Index0.16
Distance from Earth3,017.1 light-years (925.0 parsecs)
ConstellationCygnus
Discovery methodTransit
Discovery facilityKepler
Discovery year2016

Data: NASA Exoplanet Archive, last updated 2016-05-06. Earth Similarity Index: PHL @ UPR Arecibo.

Frequently Asked Questions About Kepler-818 b

Is Kepler-818 b habitable?

Kepler-818 b is not known to orbit within the habitable zone of Kepler-818, and as a Neptune-like planet it is an unlikely candidate for life as we know it.

How far away is Kepler-818 b?

Kepler-818 b is about 3,017 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 53,100,960 years to get there.

How big is Kepler-818 b compared to Earth?

Kepler-818 b has 5.11 times the radius of Earth.

How long is a year on Kepler-818 b?

One orbit around Kepler-818 takes 10.0 Earth days — short enough that 36 of its years would fit into one Earth year.

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