Key parameters at a glance
- A radius of 1.41 Earth radii
- A mass of 2.57 Earth masses
- Surface gravity around 1.29 g
- An orbital period of 3.157 days
- Semi-major axis 0.0454 AU
- Equilibrium temperature 1,791 K (1518 °C)
- Distance from Earth 3,029.95 light-years
- Earth Similarity Index 0.156
- Travel time at Voyager 1 speed 53,433,225 years
1 sibling around Kepler-1921
Kepler-1921 c shares its host star with 1 other confirmed planet. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| Kepler-1921 c this | Super-Earth | 1.41 | 2.57 | 3.157 | 1,791 | 2023 |
| Kepler-1921 b | Sub-Neptune | 2.89 | 8.72 | 20.035 | 967 | 2021 |
Kepler-1921 c Planet Profile
Physical Specs
Classification
Planet Type
Super-Earth
Discovery
Size rank in cohort
Rank by radius
#902of 1176
top 76.6%
This planet
1.41R⊕
Super-Earth median
1.60R⊕
Nearest-size peers
| Metric | Earth | Kepler-1921 c | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.41 | 11.21 |
| Mass (M⊕) | 1.00 | 2.57 | 317.83 |
| Density (g/cm³) | 5.51 | 5.04 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.29 | 2.53 |
| Insolation (S⊕) | 1.00 | 2,436.47 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 239287963
Gaia DR2
Gaia DR2 2085204015173031552
Gaia DR3
Gaia DR3 2085204015173031552
System
Kepler-1921
Percentile among Super-Earth cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 3.16 Earth days (0.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0454 AU.
Transit Fingerprint
Depth
0.005 %
Duration
3.762 h
Impact parameter b
0.001
Rp / R★
0.006453
Transit midpoint (BJD)
2,454,964.6992
Photometric dip
Transit produces a flux drop of 50 ppm lasting ≈ 3.76 h.
Extended Orbital Architecture
Planet / star radius ratio
0.006453
Semi-major axis / stellar radius
6.480
Impact parameter (b)
0.001
Transit mid-time (BJD)
2,454,964.6992
Angular separation (arcsec)
0.04890
Eq. Temperature
1,791K
(1518 °C)
Insolation (S⊕)
2,436.47
Earth = 1.00
Earth Similarity (ESI)
0.156
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. 2023Instrument
Kepler CCD Array
Publication
2023-05
Observation locale
Space
Discovery cohort
Planets confirmed in 2023 at Kepler (12 shown).
Host System: Kepler-1921
Spectral Class
F-type yellow-white
Effective Temperature
6,120 K — hotter than the Sun (5,778 K)
Estimated Age
3.39 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
2.000 R☉
Stellar Mass
1.251 M☉
Metallicity [Fe/H]
0.02
Extended Stellar Properties
Surface gravity (log g)
3.934 dex
Stellar density
0.516 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 15 bands
Astrometric Data
Parallax
1.048 mas
Total Proper Motion
15.166 mas/yr
PM Right Ascension
-4.45 mas/yr
PM Declination
-14.50 mas/yr
Galactic Cartesian (pc)
x = 0.354 · y = -0.605 · z = 0.713
Equatorial (J2000)
RA 300.31617° · Dec 45.49533°
Galactic ℓ, b
80.466° · 7.936°
Ecliptic λ, β
322.498° · 63.514°
HTM-20 index
-1129568641
Similar Worlds
Kepler-1383 b
Super-Earth · F-type yellow-white
Radius 1.41 R⊕ · 3,350.3 ly
Kepler-187 b
Super-Earth · F-type yellow-white
Radius 1.41 R⊕ · 3,728.0 ly
Kepler-127 b
Super-Earth · F-type yellow-white
Radius 1.40 R⊕ · 1,150.7 ly
Kepler-403 d
Super-Earth · F-type yellow-white
Radius 1.42 R⊕ · 2,740.6 ly
Kepler-65 b
Super-Earth · F-type yellow-white
Radius 1.42 R⊕ · 990.6 ly
Kepler-1274 b
Super-Earth · F-type yellow-white
Radius 1.42 R⊕ · 2,004.7 ly