Skip to main content

Kepler-938 b

Mini Neptune Cygnus

Kepler-938 b is a mini-Neptune orbiting Kepler-938 in the constellation Cygnus. It lies about 3,855 light-years from Earth and was discovered in 2016 using the transit method.

2.22×Earth radius
53 dOrbital period
0.37Earth similarity
3,855 lyDistance
2016Discovered

How Big Is Kepler-938 b?

Earth1.00 R⊕Kepler-938 b2.22 R⊕
Compare any two worlds side by side in the Exoplanet Explorer app ›

Kepler-938 b has a radius of 2.22 times that of Earth.

Is Kepler-938 b in the Habitable Zone?

The position of Kepler-938 b relative to the habitable zone of Kepler-938 cannot be precisely determined from the available orbital data.

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of Kepler-938: 0.621–1.474 AU (conservative: 0.787–1.398 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-938 b — one full orbit around Kepler-938 — lasts 52.6 Earth days, shorter than Mercury's 88-day year.

How Was Kepler-938 b Discovered?

Kepler-938 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-938 b?

Kepler-938 b is 3,855.3 light-years (1,182.1 parsecs) from Earth. Light arriving here tonight left the planet about 3,855 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 67,853,280 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-938 b scores 0.37, ranking #621 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: Kepler-938

Kepler-938

Surface temperature
5,533 K (Sun: 5,772 K)
Mass
0.92 M☉
Radius
0.89 R☉
Age
4.3 billion years (Sun: 4.6)

Planetary System

Kepler-938 b is the only planet known to orbit Kepler-938 so far.

Kepler-938 b — Complete Data

Radius2.220 Earth radii (0.198 Jupiter radii)
Orbital period52.63 days
Earth Similarity Index0.37
Distance from Earth3,855.3 light-years (1,182.1 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-938 b

Is Kepler-938 b habitable?

Kepler-938 b is not known to orbit within the habitable zone of Kepler-938, and as a mini-Neptune it is an unlikely candidate for life as we know it.

How far away is Kepler-938 b?

Kepler-938 b is about 3,855 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 67,853,280 years to get there.

How big is Kepler-938 b compared to Earth?

Kepler-938 b has 2.22 times the radius of Earth.

How long is a year on Kepler-938 b?

One orbit around Kepler-938 takes 52.6 Earth days.

Exoplanet Explorer app icon

Explore Kepler-938 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.

Download on the App Store