Key parameters at a glance
- A radius of 2.54 Earth radii
- A mass of 6.99 Earth masses
- Surface gravity around 1.08 g
- An orbital period of 82.534 days
- Semi-major axis 0.3104 AU
- Equilibrium temperature 260 K (-13 °C)
- Distance from Earth 1,270.58 light-years
- Earth Similarity Index 0.710
- Travel time at Voyager 1 speed 22,406,617 years
Context from the literature
The list of exoplanets detected by the Kepler space telescope contains bodies with a wide variety of properties, with significant ranges in orbital distances, masses, radii, composition, habitability, and host star type. As of June 16 2023, the Kepler space telescope and its follow-up observations have detected 2,778 planets, including hot Jupiters, super-Earths, circumbinary planets, and planets located in the circumstellar habitable zones of their host stars. Kepler has detected over 3,601 unconfirmed planet candidates and 2,165 eclipsing binary stars.
Excerpted from Wikipedia · full article
Kepler-991 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1117of 1978
top 56.4%
This planet
2.54R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-991 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.54 | 11.21 |
| Mass (M⊕) | 1.00 | 6.99 | 317.83 |
| Density (g/cm³) | 5.51 | 2.34 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.08 | 2.53 |
| Insolation (S⊕) | 1.00 | 1.37 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 28084836
Gaia DR2
Gaia DR2 2087215262455233664
Gaia DR3
Gaia DR3 2087215262455233664
System
Kepler-991
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 82.53 Earth days (22.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.3104 AU.
Transit Fingerprint
Depth
0.190 %
Duration
4.834 h
Impact parameter b
0.033
Rp / R★
0.037544
Transit midpoint (BJD)
2,455,042.1264
Photometric dip
Transit produces a flux drop of 1,895 ppm lasting ≈ 4.83 h.
Extended Orbital Architecture
Planet / star radius ratio
0.037544
Semi-major axis / stellar radius
134.800
Impact parameter (b)
0.033
Transit mid-time (BJD)
2,455,042.1264
Angular separation (arcsec)
0.79700
Eq. Temperature
260K
(-13 °C)
Insolation (S⊕)
1.37
Earth = 1.00
Earth Similarity (ESI)
0.710
0 = alien, 1 = Earth-identical
Within the conservative habitable zone — surface water would be frozen.
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-991
Spectral Class
K-type orange
Effective Temperature
4,392 K — cooler than the Sun (5,778 K)
Estimated Age
3.47 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.610 R☉
Stellar Mass
0.640 M☉
Metallicity [Fe/H]
-0.25
Extended Stellar Properties
Surface gravity (log g)
4.670 dex
Stellar density
6.803 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
2.538 mas
Total Proper Motion
21.596 mas/yr
PM Right Ascension
-14.33 mas/yr
PM Declination
-16.15 mas/yr
Galactic Cartesian (pc)
x = 0.295 · y = -0.577 · z = 0.762
Equatorial (J2000)
RA 297.09055° · Dec 49.62649°
Galactic ℓ, b
83.020° · 11.868°
Ecliptic λ, β
322.531° · 68.182°
HTM-20 index
1413371458
Similar Worlds
TOI-1648 b
Sub-Neptune · K-type orange
Radius 2.54 R⊕ · 227.8 ly
K2-118 b
Sub-Neptune · K-type orange
Radius 2.54 R⊕ · 1,049.3 ly
K2-16 c
Sub-Neptune · K-type orange
Radius 2.54 R⊕ · 1,092.5 ly
K2-119 b
Sub-Neptune · K-type orange
Radius 2.53 R⊕ · 1,192.4 ly
Kepler-156 c
Sub-Neptune · K-type orange
Radius 2.55 R⊕ · 1,446.4 ly
Kepler-577 b
Sub-Neptune · K-type orange
Radius 2.55 R⊕ · 1,709.9 ly