Key parameters at a glance
- A radius of 2.25 Earth radii
- A mass of 5.69 Earth masses
- Surface gravity around 1.12 g
- An orbital period of 14.627 days
- Semi-major axis 0.1180 AU
- Equilibrium temperature 736 K (463 °C)
- Distance from Earth 2,702.50 light-years
- Earth Similarity Index 0.358
- Travel time at Voyager 1 speed 47,658,629 years
3 siblings around Kepler-172
Kepler-172 d shares its host star with 3 other confirmed planets. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| Kepler-172 b | Sub-Neptune | 2.35 | 6.12 | 2.940 | 1,256 | 2014 |
| Kepler-172 c | Sub-Neptune | 2.86 | 8.55 | 6.389 | 970 | 2014 |
| Kepler-172 d this | Sub-Neptune | 2.25 | 5.69 | 14.627 | 736 | 2014 |
| Kepler-172 e | Sub-Neptune | 2.76 | 8.05 | 35.119 | 550 | 2014 |
Kepler-172 d Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1589of 1978
top 80.3%
This planet
2.25R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-172 d | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.25 | 11.21 |
| Mass (M⊕) | 1.00 | 5.69 | 317.83 |
| Density (g/cm³) | 5.51 | 2.74 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.12 | 2.53 |
| Insolation (S⊕) | 1.00 | 75.29 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 237157751
Gaia DR2
Gaia DR2 2104506319750394624
Gaia DR3
Gaia DR3 2104506319750394624
System
Kepler-172
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 14.63 Earth days (4.0% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1180 AU.
Transit Fingerprint
Depth
0.040 %
Duration
3.541 h
Impact parameter b
0.050
Rp / R★
0.020136
Transit midpoint (BJD)
2,454,969.2367
Photometric dip
Transit produces a flux drop of 396 ppm lasting ≈ 3.54 h.
Extended Orbital Architecture
Planet / star radius ratio
0.020136
Semi-major axis / stellar radius
17.100
Impact parameter (b)
0.050
Transit mid-time (BJD)
2,454,969.2367
Angular separation (arcsec)
0.14200
Eq. Temperature
736K
(463 °C)
Insolation (S⊕)
75.29
Earth = 1.00
Earth Similarity (ESI)
0.358
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.
Discovery Paper
Primary reference
Rowe et al. 2014Instrument
Kepler CCD Array
Publication
2014-03
Observation locale
Space
Discovery cohort
Planets confirmed in 2014 at Kepler (12 shown).
Host System: Kepler-172
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,526 K — cooler than the Sun (5,778 K)
Estimated Age
2.69 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.085 R☉
Stellar Mass
1.081 M☉
Metallicity [Fe/H]
0.39
Extended Stellar Properties
Surface gravity (log g)
4.375 dex
Stellar density
0.970 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.178 mas
Total Proper Motion
4.572 mas/yr
PM Right Ascension
0.84 mas/yr
PM Declination
4.49 mas/yr
Galactic Cartesian (pc)
x = 0.172 · y = -0.725 · z = 0.667
Equatorial (J2000)
RA 283.36841° · Dec 41.82184°
Galactic ℓ, b
71.607° · 17.348°
Ecliptic λ, β
293.303° · 64.183°
HTM-20 index
1365781898
Similar Worlds
Kepler-300 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.25 R⊕ · 3,582.7 ly
Kepler-1090 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.25 R⊕ · 2,800.9 ly
Kepler-467 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.25 R⊕ · 1,520.8 ly
Kepler-1381 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.25 R⊕ · 3,904.2 ly
Kepler-272 d
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.25 R⊕ · 2,901.5 ly
K2-355 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.25 R⊕ · 1,632.4 ly