Key parameters at a glance
- A radius of 2.89 Earth radii
- A mass of 8.70 Earth masses
- Surface gravity around 1.04 g
- An orbital period of 13.214 days
- Semi-major axis 0.1019 AU
- Equilibrium temperature 629 K (356 °C)
- Distance from Earth 3,471.83 light-years
- Earth Similarity Index 0.380
- Travel time at Voyager 1 speed 61,225,768 years
- Almost certainly tidally locked to its host star given the close orbit
Kepler-781 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#640of 1978
top 32.3%
This planet
2.89R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-781 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.89 | 11.21 |
| Mass (M⊕) | 1.00 | 8.70 | 317.83 |
| Density (g/cm³) | 5.51 | 1.98 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.04 | 2.53 |
| Insolation (S⊕) | 1.00 | 44.40 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 158489897
Gaia DR2
Gaia DR2 2130857627739052928
Gaia DR3
Gaia DR3 2130857627739052928
System
Kepler-781
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 13.21 Earth days (3.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1019 AU.
Transit Fingerprint
Depth
0.115 %
Duration
3.424 h
Impact parameter b
0.850
Rp / R★
0.034346
Transit midpoint (BJD)
2,454,973.5873
Photometric dip
Transit produces a flux drop of 1,155 ppm lasting ≈ 3.42 h.
Extended Orbital Architecture
Planet / star radius ratio
0.034346
Semi-major axis / stellar radius
16.800
Impact parameter (b)
0.850
Transit mid-time (BJD)
2,454,973.5873
Angular separation (arcsec)
0.09570
Eq. Temperature
629K
(356 °C)
Insolation (S⊕)
44.40
Earth = 1.00
Earth Similarity (ESI)
0.380
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.
Discovery Paper
Primary reference
Morton et al. 2016Instrument
Kepler CCD Array
Publication
2016-05
Observation locale
Space
Discovery cohort
Planets confirmed in 2016 at Kepler (12 shown).
Host System: Kepler-781
Spectral Class
K-type orange
Effective Temperature
5,162 K — cooler than the Sun (5,778 K)
Estimated Age
4.90 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.780 R☉
Stellar Mass
0.810 M☉
Metallicity [Fe/H]
-0.10
Extended Stellar Properties
Surface gravity (log g)
4.580 dex
Stellar density
1.849 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
0.911 mas
Total Proper Motion
11.541 mas/yr
PM Right Ascension
-5.80 mas/yr
PM Declination
-9.98 mas/yr
Galactic Cartesian (pc)
x = 0.205 · y = -0.645 · z = 0.736
Equatorial (J2000)
RA 287.65359° · Dec 47.41478°
Galactic ℓ, b
78.217° · 16.582°
Ecliptic λ, β
304.483° · 68.750°
HTM-20 index
-1849106080
Similar Worlds
K2-255 b
Sub-Neptune · K-type orange
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Kepler-391 c
Sub-Neptune · K-type orange
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K2-378 b
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Kepler-716 b
Sub-Neptune · K-type orange
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Kepler-1684 b
Sub-Neptune · K-type orange
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KOBE-1 b
Sub-Neptune · K-type orange
Radius 2.91 R⊕ · 78.2 ly