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Kepler-1201 b

Mini Neptune Cygnus

Kepler-1201 b is a mini-Neptune orbiting Kepler-1201 in the constellation Cygnus. It lies about 3,080 light-years from Earth and was discovered in 2016 using the transit method.

2.29×Earth radius
15 dOrbital period
0.26Earth similarity
3,080 lyDistance
2016Discovered

How Big Is Kepler-1201 b?

Earth1.00 R⊕Kepler-1201 b2.29 R⊕
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Kepler-1201 b has a radius of 2.29 times that of Earth.

Is Kepler-1201 b in the Habitable Zone?

The position of Kepler-1201 b relative to the habitable zone of Kepler-1201 cannot be precisely determined from the available orbital data.

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of Kepler-1201: 1.038–2.423 AU (conservative: 1.315–2.297 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 Kepler-1201 b — one full orbit around Kepler-1201 — lasts 15.2 Earth days, shorter than Mercury's 88-day year.

How Was Kepler-1201 b Discovered?

Kepler-1201 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-1201 b?

Kepler-1201 b is 3,079.7 light-years (944.2 parsecs) from Earth. Light arriving here tonight left the planet about 3,080 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 54,202,720 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-1201 b scores 0.26, ranking #2,946 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: Kepler-1201

Kepler-1201

Surface temperature
6,177 K (Sun: 5,772 K)
Mass
1.15 M☉
Radius
1.24 R☉
Age
3.0 billion years (Sun: 4.6)

Planetary System

Kepler-1201 b is the only planet known to orbit Kepler-1201 so far.

Kepler-1201 b — Complete Data

Radius2.290 Earth radii (0.204 Jupiter radii)
Orbital period15.19 days
Earth Similarity Index0.26
Distance from Earth3,079.7 light-years (944.2 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-1201 b

Is Kepler-1201 b habitable?

Kepler-1201 b is not known to orbit within the habitable zone of Kepler-1201, and as a mini-Neptune it is an unlikely candidate for life as we know it.

How far away is Kepler-1201 b?

Kepler-1201 b is about 3,080 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 54,202,720 years to get there.

How big is Kepler-1201 b compared to Earth?

Kepler-1201 b has 2.29 times the radius of Earth.

How long is a year on Kepler-1201 b?

One orbit around Kepler-1201 takes 15.2 Earth days — short enough that 24 of its years would fit into one Earth year.

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