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Kepler-739 b

Sub Neptune Cygnus

Kepler-739 b is a sub-Neptune orbiting Kepler-739 in the constellation Cygnus. It lies about 4,471 light-years from Earth and was discovered in 2016 using the transit method.

3.32×Earth radius
13 dOrbital period
0.21Earth similarity
4,471 lyDistance
2016Discovered

How Big Is Kepler-739 b?

Earth1.00 R⊕Kepler-739 b3.32 R⊕
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Kepler-739 b has a radius of 3.32 times that of Earth.

Is Kepler-739 b in the Habitable Zone?

The position of Kepler-739 b relative to the habitable zone of Kepler-739 cannot be precisely determined from the available orbital data.

Too hot Optimistic habitable zone Conservative habitable zone Too cold

Habitable zone of Kepler-739: 0.641–1.519 AU (conservative: 0.812–1.440 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-739 b — one full orbit around Kepler-739 — lasts 12.5 Earth days, shorter than Mercury's 88-day year.

How Was Kepler-739 b Discovered?

Kepler-739 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-739 b?

Kepler-739 b is 4,470.5 light-years (1,370.7 parsecs) from Earth. Light arriving here tonight left the planet about 4,471 years ago. A probe traveling at the speed of Voyager 1 — about 17 km/s, the fastest outbound spacecraft ever launched — would need roughly 78,680,800 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-739 b scores 0.21, ranking #3,765 of 5,568 planets with a known ESI. For reference, Mars scores about 0.70.

The Host Star: Kepler-739

Kepler-739

Surface temperature
5,601 K (Sun: 5,772 K)
Mass
0.93 M☉
Radius
0.90 R☉
Age
4.3 billion years (Sun: 4.6)

Planetary System

Kepler-739 b is the only planet known to orbit Kepler-739 so far.

Kepler-739 b — Complete Data

Radius3.320 Earth radii (0.296 Jupiter radii)
Orbital period12.53 days
Earth Similarity Index0.21
Distance from Earth4,470.5 light-years (1,370.7 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-739 b

Is Kepler-739 b habitable?

Kepler-739 b is not known to orbit within the habitable zone of Kepler-739, and as a sub-Neptune it is an unlikely candidate for life as we know it.

How far away is Kepler-739 b?

Kepler-739 b is about 4,471 light-years from Earth in the constellation Cygnus. A spacecraft traveling as fast as Voyager 1 (about 17 km/s) would need roughly 78,680,800 years to get there.

How big is Kepler-739 b compared to Earth?

Kepler-739 b has 3.32 times the radius of Earth.

How long is a year on Kepler-739 b?

One orbit around Kepler-739 takes 12.5 Earth days — short enough that 29 of its years would fit into one Earth year.

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