Key parameters at a glance

A radius of 1.07 Earth radii
A mass of 1.25 Earth masses
Surface gravity around 1.09 g
An orbital period of 1.211 days
Semi-major axis 0.0207 AU
Equilibrium temperature 1,351 K (1078 °C)
Distance from Earth 725.19 light-years
Earth Similarity Index 0.229
Travel time at Voyager 1 speed 12,788,752 years
Almost certainly tidally locked to its host star given the close orbit

Kepler-1698 b Planet Profile

Physical Specs

Radius

1.07 R⊕

Radius (Jupiter)

0.096 R♃

Mass

1.25 M⊕

Mass (Jupiter)

0.004 M♃

Density

5.56 g/cm³

Surface Gravity

1.09 g (Earth)

Classification

Planet Type

Rocky Terrestrial

ESI Score 0.229

HZ Position Inner

Controversial No

Discovery

Year 2020

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#259of 570

top 45.3%

This planet

1.07R⊕

Rocky Terrestrial median

1.01R⊕

Nearest-size peers

HD 63433 d 1.07 R⊕ TOI-700 d 1.07 R⊕ K2-381 b 1.08 R⊕

Metric	Earth	Kepler-1698 b	Jupiter
Radius (R⊕)	1.00	1.07	11.21
Mass (M⊕)	1.00	1.25	317.83
Density (g/cm³)	5.51	5.56	1.33
Surface Gravity (g)	1.00	1.09	2.53
Insolation (S⊕)	1.00	697.60	0.037

Star Catalogue Identifiers

TIC

TIC 138105005

Gaia DR2

Gaia DR2 2052368955838887808

Gaia DR3

Gaia DR3 2052368955838887808

System

Kepler-1698

Percentile among Rocky Terrestrial cohort

Radius 1.073 R⊕ · percentile 55 / cohort 570

Mass 1.250 M⊕ · percentile 49 / cohort 570

Orbital period 1.21 d · percentile 13 / cohort 567

Distance 222.35 pc · percentile 33 / cohort 566

ESI 0.229 · percentile 19 / cohort 570

Orbit & Habitability

Orbital Dynamics

Period

1.211 days

Semi-major axis

0.0207 AU

Eccentricity

0.000

Inclination

83.56 °

Year Length

A year here lasts approximately 1.21 Earth days (0.3% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0207 AU.

Transit Fingerprint

Depth

0.016 %

Duration

1.434 h

Impact parameter b

0.597

Rp / R★

0.011980

Transit midpoint (BJD)

2,454,965.3932

Photometric dip

Transit produces a flux drop of 159 ppm lasting ≈ 1.43 h.

Extended Orbital Architecture

Planet / star radius ratio

0.011980

Semi-major axis / stellar radius

3.401

Impact parameter (b)

0.597

Transit mid-time (BJD)

2,454,965.3932

Angular separation (arcsec)

0.09290

Eq. Temperature

1,351K

(1078 °C)

Insolation (S⊕)

697.60

Earth = 1.00

Earth Similarity (ESI)

0.229

0 = alien, 1 = Earth-identical

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

Discovery Paper

Primary reference

Armstrong et al. 2021

Instrument

Kepler CCD Array

Publication

2021-07

Observation locale

Space

Discovery cohort

Planets confirmed in 2020 at Kepler (12 shown).

Kepler-1649 c · Rocky Terrestrial Kepler-1701 b · Sub-Neptune Kepler-1690 b · Sub-Neptune Kepler-1700 b · Sub-Neptune Kepler-1684 b · Sub-Neptune Kepler-1678 b · Sub-Neptune Kepler-598 c · Sub-Neptune Kepler-1661 b · Sub-Neptune Kepler-1663 b · Sub-Neptune Kepler-1681 b · Sub-Neptune Kepler-1672 b · Sub-Neptune Kepler-1702 b · Super-Earth

Host System: Kepler-1698

Spectral Class

K-type orange

Effective Temperature

4,975 K — cooler than the Sun (5,778 K)

Estimated Age

1.66 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.742 R☉

Stellar Mass

0.822 M☉

Metallicity [Fe/H]

0.08

Extended Stellar Properties

Surface gravity (log g)

4.613 dex

Stellar density

2.840 g/cm³

Systemic radial velocity

10.55 km/s

Metallicity ratio

[M/H]

Distance

222.35 parsec

Light-years 725.19 ly

V-band magnitude

13.05 mag

Voyager-speed travel 12,788,752 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

4.469 mas

Total Proper Motion

14.625 mas/yr

PM Right Ascension

5.88 mas/yr

PM Declination

-13.39 mas/yr

Galactic Cartesian (pc)

x = 0.307 · y = -0.711 · z = 0.633

Equatorial (J2000)

RA 293.34502° · Dec 39.25775°

Galactic ℓ, b

72.424° · 9.389°

Ecliptic λ, β

307.450° · 59.698°

HTM-20 index

1252302294