Key parameters at a glance

A radius of 2.10 Earth radii
A mass of 5.07 Earth masses
Surface gravity around 1.15 g
An orbital period of 3.607 days
Semi-major axis 0.0452 AU
Equilibrium temperature 1,046 K (773 °C)
Distance from Earth 1,328.16 light-years
Earth Similarity Index 0.254
Travel time at Voyager 1 speed 23,422,090 years

Kepler-1870 b Planet Profile

Physical Specs

Radius

2.10 R⊕

Radius (Jupiter)

0.187 R♃

Mass

5.07 M⊕

Mass (Jupiter)

0.016 M♃

Density

3.00 g/cm³

Surface Gravity

1.15 g (Earth)

Classification

Planet Type

Sub-Neptune

ESI Score 0.254

HZ Position Inner

Controversial No

Discovery

Year 2021

Method Transit

Facility Kepler

Telescope 0.95 m Kepler Telescope

Size rank in cohort

Rank by radius

#1817of 1978

top 91.8%

This planet

2.10R⊕

Sub-Neptune median

2.71R⊕

Nearest-size peers

TOI-5734 b 2.10 R⊕ Kepler-52 b 2.10 R⊕ Kepler-360 c 2.10 R⊕

Metric	Earth	Kepler-1870 b	Jupiter
Radius (R⊕)	1.00	2.10	11.21
Mass (M⊕)	1.00	5.07	317.83
Density (g/cm³)	5.51	3.00	1.33
Surface Gravity (g)	1.00	1.15	2.53
Insolation (S⊕)	1.00	287.60	0.037

Star Catalogue Identifiers

TIC

TIC 138433618

Gaia DR2

Gaia DR2 2077299694799977856

Gaia DR3

Gaia DR3 2077299694799977856

System

Kepler-1870

Percentile among Sub-Neptune cohort

Radius 2.101 R⊕ · percentile 8 / cohort 1978

Mass 5.070 M⊕ · percentile 9 / cohort 1978

Orbital period 3.61 d · percentile 7 / cohort 1946

Distance 407.22 pc · percentile 42 / cohort 1975

ESI 0.254 · percentile 17 / cohort 1978

Orbit & Habitability

Orbital Dynamics

Period

3.607 days

Semi-major axis

0.0452 AU

Eccentricity

0.000

Inclination

86.68 °

Year Length

A year here lasts approximately 3.61 Earth days (1.0% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0452 AU.

Transit Fingerprint

Depth

0.043 %

Duration

1.026 h

Impact parameter b

0.109

Rp / R★

0.019009

Transit midpoint (BJD)

2,454,956.9531

Photometric dip

Transit produces a flux drop of 432 ppm lasting ≈ 1.03 h.

Extended Orbital Architecture

Planet / star radius ratio

0.019009

Semi-major axis / stellar radius

10.800

Impact parameter (b)

0.109

Transit mid-time (BJD)

2,454,956.9531

Angular separation (arcsec)

0.11100

Eq. Temperature

1,046K

(773 °C)

Insolation (S⊕)

287.60

Earth = 1.00

Earth Similarity (ESI)

0.254

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. 2022

Instrument

Kepler CCD Array

Publication

2022-02

Observation locale

Space

Discovery cohort

Planets confirmed in 2021 at Kepler (12 shown).

Kepler-1816 b · Super-Earth Kepler-1705 c · Sub-Neptune Kepler-1948 b · Rocky Terrestrial Kepler-196 d · Sub-Neptune Kepler-1853 b · Super-Earth Kepler-1840 b · Sub-Neptune Kepler-1881 b · Sub-Neptune Kepler-1858 b · Sub-Neptune Kepler-1874 b · Sub-Neptune Kepler-1802 c · Sub-Neptune Kepler-1749 b · Super-Earth Kepler-1849 b · Sub-Neptune

Host System: Kepler-1870

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,508 K — cooler than the Sun (5,778 K)

Estimated Age

0.79 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.840 R☉

Stellar Mass

0.955 M☉

Metallicity [Fe/H]

0.07

Extended Stellar Properties

Surface gravity (log g)

4.569 dex

Stellar density

4.689 g/cm³

Metallicity ratio

[Fe/H]

Distance

407.22 parsec

Light-years 1,328.16 ly

V-band magnitude

13.57 mag

Voyager-speed travel 23,422,090 yr

Multi-band Host Photometry — 16 bands

Astrometric Data

Parallax

2.427 mas

Total Proper Motion

6.742 mas/yr

PM Right Ascension

3.75 mas/yr

PM Declination

-5.61 mas/yr

Galactic Cartesian (pc)

x = 0.308 · y = -0.694 · z = 0.651

Equatorial (J2000)

RA 293.93351° · Dec 40.59070°

Galactic ℓ, b

73.834° · 9.606°

Ecliptic λ, β

309.176° · 60.815°

HTM-20 index

2101339279