Key parameters at a glance

A radius of 0.60 Earth radii
A mass of 0.16 Earth masses
Surface gravity around 0.43 g
An orbital period of 3.033 days
Semi-major axis 0.0405 AU
Equilibrium temperature 1,187 K (914 °C)
Distance from Earth 1,112.08 light-years
Earth Similarity Index 0.230
Travel time at Voyager 1 speed 19,611,491 years

Kepler-1998 b Planet Profile

Physical Specs

Radius

0.60 R⊕

Radius (Jupiter)

0.054 R♃

Mass

0.16 M⊕

Mass (Jupiter)

0.000 M♃

Density

3.97 g/cm³

Surface Gravity

0.43 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.230

HZ Position Inner

Controversial No

Discovery

Year 2023

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#550of 570

top 96.3%

This planet

0.60R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

Kepler-1583 b 0.60 R⊕ Kepler-963 c 0.60 R⊕ KOI-1843.03 0.61 R⊕

Metric	Earth	Kepler-1998 b	Jupiter
Radius (R⊕)	1.00	0.60	11.21
Mass (M⊕)	1.00	0.16	317.83
Density (g/cm³)	5.51	3.97	1.33
Surface Gravity (g)	1.00	0.43	2.53
Insolation (S⊕)	1.00	468.31	0.037

Star Catalogue Identifiers

TIC

TIC 164525250

Gaia DR2

Gaia DR2 2107658516506930048

Gaia DR3

Gaia DR3 2107658516506930048

System

Kepler-1998

Percentile among Rocky Terrestrial cohort

Radius 0.600 R⊕ · percentile 3 / cohort 570

Mass 0.156 M⊕ · percentile 2 / cohort 570

Orbital period 3.03 d · percentile 34 / cohort 567

Distance 340.97 pc · percentile 46 / cohort 566

ESI 0.230 · percentile 20 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

3.033 days

Semi-major axis

0.0405 AU

Eccentricity

0.000

Inclination

88.93 °

Year Length

A year here lasts approximately 3.03 Earth days (0.8% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0405 AU.

Transit Fingerprint

Depth

0.004 %

Duration

1.774 h

Impact parameter b

0.238

Rp / R★

0.005931

Transit midpoint (BJD)

2,454,967.0668

Photometric dip

Transit produces a flux drop of 42 ppm lasting ≈ 1.77 h.

Extended Orbital Architecture

Planet / star radius ratio

0.005931

Semi-major axis / stellar radius

12.780

Impact parameter (b)

0.238

Transit mid-time (BJD)

2,454,967.0668

Angular separation (arcsec)

0.11900

Eq. Temperature

1,187K

(914 °C)

Insolation (S⊕)

468.31

Earth = 1.00

Earth Similarity (ESI)

0.230

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

Discovery Paper

Primary reference

Valizadegan et al. 2023

Instrument

Kepler CCD Array

Publication

2023-05

Observation locale

Space

Discovery cohort

Planets confirmed in 2023 at Kepler (12 shown).

Kepler-1126 c · Super-Earth Kepler-2000 c · Super-Earth Kepler-1052 c · Sub-Neptune Kepler-311 d · Sub-Neptune Kepler-1996 c · Sub-Neptune Kepler-1162 c · Super-Earth Kepler-1996 b · Sub-Neptune Kepler-1610 c · Sub-Neptune Kepler-1801 c · Sub-Neptune Kepler-1995 b · Neptune-like Kepler-1992 b · Rocky Terrestrial Kepler-1986 b · Super-Earth

Host System: Kepler-1998

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,640 K — cooler than the Sun (5,778 K)

Estimated Age

4.27 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.921 R☉

Stellar Mass

0.962 M☉

Metallicity [Fe/H]

0.06

Extended Stellar Properties

Surface gravity (log g)

4.492 dex

Stellar density

4.291 g/cm³

Metallicity ratio

[Fe/H]

Distance

340.97 parsec

Light-years 1,112.08 ly

V-band magnitude

12.74 mag

Voyager-speed travel 19,611,491 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

2.904 mas

Total Proper Motion

18.663 mas/yr

PM Right Ascension

-0.57 mas/yr

PM Declination

-18.65 mas/yr

Galactic Cartesian (pc)

x = 0.157 · y = -0.656 · z = 0.738

Equatorial (J2000)

RA 283.42915° · Dec 47.59240°

Galactic ℓ, b

77.323° · 19.312°

Ecliptic λ, β

296.941° · 69.779°

HTM-20 index

1591997169