Key parameters at a glance

A radius of 2.50 Earth radii
A mass of 6.80 Earth masses
Surface gravity around 1.09 g
An orbital period of 24.587 days
Semi-major axis 0.1552 AU
Equilibrium temperature 530 K (257 °C)
Distance from Earth 3,632.24 light-years
Earth Similarity Index 0.471
Travel time at Voyager 1 speed 64,054,483 years

Kepler-738 b Planet Profile

Physical Specs

Radius

2.50 R⊕

Radius (Jupiter)

0.223 R♃

Mass

6.80 M⊕

Mass (Jupiter)

0.021 M♃

Density

2.39 g/cm³

Surface Gravity

1.09 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.471

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1168of 1978

top 59.0%

This planet

2.50R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

Kepler-126 d 2.50 R⊕ Kepler-254 d 2.50 R⊕ GJ 163 c 2.50 R⊕

Metric	Earth	Kepler-738 b	Jupiter
Radius (R⊕)	1.00	2.50	11.21
Mass (M⊕)	1.00	6.80	317.83
Density (g/cm³)	5.51	2.39	1.33
Surface Gravity (g)	1.00	1.09	2.53
Insolation (S⊕)	1.00	27.64	0.037

Star Catalogue Identifiers

TIC

TIC 158490928

Gaia DR2

Gaia DR2 2130427821771278976

Gaia DR3

Gaia DR3 2130427821771278976

System

Kepler-738

Percentile among Sub-Neptune cohort

Radius 2.500 R⊕ · percentile 40 / cohort 1978

Mass 6.800 M⊕ · percentile 37 / cohort 1978

Orbital period 24.59 d · percentile 69 / cohort 1946

Distance 1,113.65 pc · percentile 84 / cohort 1975

ESI 0.471 · percentile 66 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

24.587 days

Semi-major axis

0.1552 AU

Eccentricity

0.000

Inclination

89.02 °

Year Length

A year here lasts approximately 24.59 Earth days (6.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1552 AU.

Transit Fingerprint

Depth

0.091 %

Duration

3.867 h

Impact parameter b

0.109

Rp / R★

0.028227

Transit midpoint (BJD)

2,455,006.7039

Photometric dip

Transit produces a flux drop of 908 ppm lasting ≈ 3.87 h.

Extended Orbital Architecture

Planet / star radius ratio

0.028227

Semi-major axis / stellar radius

49.670

Impact parameter (b)

0.109

Transit mid-time (BJD)

2,455,006.7039

Angular separation (arcsec)

0.13900

Eq. Temperature

530K

(257 °C)

Insolation (S⊕)

27.64

Earth = 1.00

Earth Similarity (ESI)

0.471

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.

Discovery Paper

Primary reference

Morton et al. 2016

Instrument

Kepler CCD Array

Publication

2016-05

Observation locale

Space

Discovery cohort

Planets confirmed in 2016 at Kepler (12 shown).

Kepler-1512 b · Rocky Terrestrial Kepler-1410 b · Super-Earth Kepler-560 b · Super-Earth Kepler-1389 b · Super-Earth Kepler-1450 b · Super-Earth Kepler-1544 b · Super-Earth Kepler-1459 b · Super-Earth Kepler-1638 b · Super-Earth Kepler-737 b · Super-Earth Kepler-1185 b · Super-Earth Kepler-1178 b · Rocky Terrestrial Kepler-1040 b · Sub-Neptune

Host System: Kepler-738

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,327 K — cooler than the Sun (5,778 K)

Estimated Age

4.57 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.820 R☉

Stellar Mass

0.860 M☉

Metallicity [Fe/H]

-0.09

Extended Stellar Properties

Surface gravity (log g)

4.550 dex

Stellar density

3.834 g/cm³

Metallicity ratio

[Fe/H]

Distance

1,113.65 parsec

Light-years 3,632.24 ly

V-band magnitude

15.79 mag

Voyager-speed travel 64,054,483 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

0.870 mas

Total Proper Motion

5.578 mas/yr

PM Right Ascension

0.86 mas/yr

PM Declination

5.51 mas/yr

Galactic Cartesian (pc)

x = 0.208 · y = -0.655 · z = 0.726

Equatorial (J2000)

RA 287.56965° · Dec 46.56790°

Galactic ℓ, b

77.378° · 16.313°

Ecliptic λ, β

303.586° · 67.969°

HTM-20 index

-1693657284