Key parameters at a glance
- A radius of 2.78 Earth radii
- A mass of 8.13 Earth masses
- Surface gravity around 1.05 g
- An orbital period of 131.190 days
- Semi-major axis 0.4621 AU
- Equilibrium temperature 284 K (11 °C)
- Distance from Earth 1,673.53 light-years
- Earth Similarity Index 0.730
- Travel time at Voyager 1 speed 29,512,687 years
Kepler-1840 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#777of 1978
top 39.2%
This planet
2.78R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-1840 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.78 | 11.21 |
| Mass (M⊕) | 1.00 | 8.13 | 317.83 |
| Density (g/cm³) | 5.51 | 2.08 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.05 | 2.53 |
| Insolation (S⊕) | 1.00 | 1.30 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 171090560
Gaia DR2
Gaia DR2 2075338028623847168
Gaia DR3
Gaia DR3 2075338028623847168
System
Kepler-1840
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 131.19 Earth days (35.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.4621 AU.
Transit Fingerprint
Depth
0.092 %
Duration
7.548 h
Impact parameter b
0.069
Rp / R★
0.026732
Transit midpoint (BJD)
2,455,005.3923
Photometric dip
Transit produces a flux drop of 916 ppm lasting ≈ 7.55 h.
Extended Orbital Architecture
Planet / star radius ratio
0.026732
Semi-major axis / stellar radius
148.700
Impact parameter (b)
0.069
Transit mid-time (BJD)
2,455,005.3923
Angular separation (arcsec)
0.90100
Eq. Temperature
284K
(11 °C)
Insolation (S⊕)
1.30
Earth = 1.00
Earth Similarity (ESI)
0.730
0 = alien, 1 = Earth-identical
Within the conservative habitable zone — liquid water is physically possible with adequate atmospheric pressure.
Discovery Paper
Primary reference
Valizadegan et al. 2022Instrument
Kepler CCD Array
Publication
2022-02
Observation locale
Space
Discovery cohort
Planets confirmed in 2021 at Kepler (12 shown).
Host System: Kepler-1840
Spectral Class
K-type orange
Effective Temperature
4,898 K — cooler than the Sun (5,778 K)
Estimated Age
14.00 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.803 R☉
Stellar Mass
0.774 M☉
Metallicity [Fe/H]
0.14
Extended Stellar Properties
Surface gravity (log g)
4.518 dex
Stellar density
3.613 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.920 mas
Total Proper Motion
11.947 mas/yr
PM Right Ascension
10.90 mas/yr
PM Declination
4.89 mas/yr
Galactic Cartesian (pc)
x = 0.359 · y = -0.658 · z = 0.662
Equatorial (J2000)
RA 298.59488° · Dec 41.43596°
Galactic ℓ, b
76.303° · 6.939°
Ecliptic λ, β
316.480° · 60.344°
HTM-20 index
-28302033
Similar Worlds
Kepler-531 b
Sub-Neptune · K-type orange
Radius 2.78 R⊕ · 824.4 ly
K2-284 b
Sub-Neptune · K-type orange
Radius 2.78 R⊕ · 349.9 ly
Kepler-1669 b
Sub-Neptune · K-type orange
Radius 2.78 R⊕ · 1,772.5 ly
TOI-444 b
Sub-Neptune · K-type orange
Radius 2.77 R⊕ · 187.2 ly
Kepler-1140 b
Sub-Neptune · K-type orange
Radius 2.77 R⊕ · 2,141.1 ly
HD 73583 b
Sub-Neptune · K-type orange
Radius 2.79 R⊕ · 103.0 ly