Key parameters at a glance

A radius of 2.04 Earth radii
A mass of 7.93 Earth masses
Surface gravity around 1.91 g
An orbital period of 42.896 days
Semi-major axis 0.2330 AU
Equilibrium temperature 448 K (175 °C)
Distance from Earth 1,000.44 light-years
Earth Similarity Index 0.618
Travel time at Voyager 1 speed 17,642,836 years
Almost certainly tidally locked to its host star given the close orbit

4 siblings around Kepler-48

Kepler-48 d shares its host star with 4 other confirmed planets. Side-by-side measurements below.

Planet	Type	Radius (R⊕)	Mass (M⊕)	Period (d)	Eq. T (K)	Year
Kepler-48 b	Super-Earth	1.88	3.94	4.778	932	2012
Kepler-48 c	Sub-Neptune	2.71	14.61	9.674	736	2012
Kepler-48 d this	Sub-Neptune	2.04	7.93	42.896	448	2014
Kepler-48 e	Gas Giant	13.40	657.00	982.000	—	2014
Kepler-48 f	Gas Giant	13.80	298.58	5,219.682	—	2023

Kepler-48 d Planet Profile

Physical Specs

Radius

2.04 R⊕

Radius (Jupiter)

0.182 R♃

Mass

7.93 M⊕

Mass (Jupiter)

0.025 M♃

Density

5.08 g/cm³

Surface Gravity

1.91 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.618

HZ Position Inner

Controversial No

Discovery

Year 2014

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1904of 1978

top 96.2%

This planet

2.04R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

HD 20794 d 2.04 R⊕ TOI-2081 b 2.04 R⊕ Kepler-230 c 2.04 R⊕

Metric	Earth	Kepler-48 d	Jupiter
Radius (R⊕)	1.00	2.04	11.21
Mass (M⊕)	1.00	7.93	317.83
Density (g/cm³)	5.51	5.08	1.33
Surface Gravity (g)	1.00	1.91	2.53
Insolation (S⊕)	1.00	9.29	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	7.930 M⊕	Direct mass measurement (not derived).
Minimum mass (M sin i)	8.891 M⊕	Lower bound from radial-velocity fitting.

Star Catalogue Identifiers

TIC

TIC 171882123

Gaia DR2

Gaia DR2 2075112109039378688

Gaia DR3

Gaia DR3 2075112109039378688

System

Kepler-48

Percentile among Sub-Neptune cohort

Radius 2.040 R⊕ · percentile 3 / cohort 1978

Mass 7.930 M⊕ · percentile 54 / cohort 1978

Orbital period 42.90 d · percentile 82 / cohort 1946

Distance 306.74 pc · percentile 35 / cohort 1975

ESI 0.618 · percentile 84 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

42.896 days

Semi-major axis

0.2330 AU

Eccentricity

0.000

Inclination

89.99 °

Year Length

A year here lasts approximately 42.90 Earth days (11.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.2330 AU.

Transit Fingerprint

Depth

0.056 %

Duration

5.625 h

Impact parameter b

0.200

Rp / R★

0.021021

Transit midpoint (BJD)

2,454,979.0655

Photometric dip

Transit produces a flux drop of 555 ppm lasting ≈ 5.63 h.

Extended Orbital Architecture

Planet / star radius ratio

0.021021

Semi-major axis / stellar radius

59.500

Impact parameter (b)

0.200

RV semi-amplitude (K)

1.570 m/s

Transit mid-time (BJD)

2,454,979.0655

Angular separation (arcsec)

0.76000

Eq. Temperature

448K

(175 °C)

Insolation (S⊕)

9.29

Earth = 1.00

Earth Similarity (ESI)

0.618

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Discovery Paper

Primary reference

Marcy et al. 2014

Instrument

Kepler CCD Array

Publication

2014-02

Observation locale

Space

Discovery cohort

Planets confirmed in 2014 at Kepler (12 shown).

Kepler-186 e · Super-Earth Kepler-395 c · Super-Earth Kepler-220 e · Super-Earth Kepler-249 d · Super-Earth Kepler-296 f · Super-Earth Kepler-367 c · Rocky Terrestrial Kepler-296 e · Super-Earth Kepler-155 c · Sub-Neptune Kepler-138 d · Super-Earth Kepler-333 c · Rocky Terrestrial Kepler-331 d · Super-Earth Kepler-267 d · Sub-Neptune

Host System: Kepler-48

Spectral Class

K-type orange

Effective Temperature

5,194 K — cooler than the Sun (5,778 K)

Estimated Age

3.14 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.890 R☉

Stellar Mass

0.880 M☉

Metallicity [Fe/H]

0.17

Extended Stellar Properties

Surface gravity (log g)

4.487 dex

Stellar density

1.980 g/cm³

Systemic radial velocity

-10.53 km/s

Rotational v·sin i

0.50 km/s

Metallicity ratio

[Fe/H]

Distance

306.74 parsec

Light-years 1,000.44 ly

V-band magnitude

13.17 mag

Voyager-speed travel 17,642,836 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

3.231 mas

Total Proper Motion

24.275 mas/yr

PM Right Ascension

13.23 mas/yr

PM Declination

-20.36 mas/yr

Galactic Cartesian (pc)

x = 0.368 · y = -0.660 · z = 0.655

Equatorial (J2000)

RA 299.13931° · Dec 40.94894°

Galactic ℓ, b

76.090° · 6.339°

Ecliptic λ, β

316.862° · 59.737°

HTM-20 index

-213247919

Similar Worlds

Kepler-845 b

Sub-Neptune · K-type orange

Radius 2.04 R⊕ · 1,405.9 ly

Kepler-324 e

Sub-Neptune · K-type orange

Radius 2.04 R⊕ · 1,635.9 ly

Wolf 503 b

Sub-Neptune · K-type orange

Radius 2.04 R⊕ · 145.2 ly

TOI-712 b

Sub-Neptune · K-type orange

Radius 2.05 R⊕ · 191.2 ly

Kepler-1461 b

Sub-Neptune · K-type orange

Radius 2.03 R⊕ · 2,214.9 ly

Kepler-161 c

Sub-Neptune · K-type orange

Radius 2.05 R⊕ · 1,417.6 ly

Explore Related Categories

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