Key parameters at a glance
- A radius of 1.19 Earth radii
- A mass of 9.20 Earth masses
- Surface gravity around 6.50 g
- An orbital period of 21.185 days
- Semi-major axis 0.1425 AU
- Equilibrium temperature 785 K (512 °C)
- Distance from Earth 2,893.21 light-years
- Earth Similarity Index 0.338
- Travel time at Voyager 1 speed 51,021,799 years
1 sibling around KOI-3503
KOI-3503 b 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 |
|---|---|---|---|---|---|---|
| KOI-3503 b this | Rocky Terrestrial | 1.19 | 9.20 | 21.185 | 785 | 2021 |
| KOI-3503 c | Rocky Terrestrial | 1.21 | 10.36 | 31.828 | 686 | 2021 |
KOI-3503 b Planet Profile
Physical Specs
Classification
Planet Type
Rocky Terrestrial
Discovery
Size rank in cohort
Rank by radius
#101of 570
top 17.5%
This planet
1.19R⊕
Rocky Terrestrial median
1.01R⊕
Nearest-size peers
| Metric | Earth | KOI-3503 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.19 | 11.21 |
| Mass (M⊕) | 1.00 | 9.20 | 317.83 |
| Density (g/cm³) | 5.51 | 10.00 | 1.33 |
| Surface Gravity (g) | 1.00 | 6.50 | 2.53 |
| Insolation (S⊕) | 1.00 | 90.20 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 9.200 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 138097784
Gaia DR2
Gaia DR2 2077601373302068352
Gaia DR3
Gaia DR3 2077601373302068352
System
KOI-3503
Percentile among Rocky Terrestrial cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 21.19 Earth days (5.8% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1425 AU.
Transit Fingerprint
Depth
0.007 %
Duration
2.776 h
Impact parameter b
0.033
Rp / R★
0.008331
Transit midpoint (BJD)
2,454,981.8096
Photometric dip
Transit produces a flux drop of 72 ppm lasting ≈ 2.78 h.
Extended Orbital Architecture
Planet / star radius ratio
0.008331
Semi-major axis / stellar radius
58.769
Impact parameter (b)
0.033
Transit mid-time (BJD)
2,454,981.8096
Angular separation (arcsec)
0.16100
Eq. Temperature
785K
(512 °C)
Insolation (S⊕)
90.20
Earth = 1.00
Earth Similarity (ESI)
0.338
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.
Detection Signatures
Transit photometry
A transit dip has been observed from at least one telescope.
Transit timing variations
Gravitational interactions from neighbours have been detected.
Discovery Paper
Primary reference
Jontof Hutter et al. 2021Instrument
Kepler CCD Array
Publication
2021-05
Observation locale
Space
Discovery cohort
Planets confirmed in 2021 at Kepler (12 shown).
Host System: KOI-3503
Spectral Class
F-type yellow-white
Effective Temperature
6,001 K — hotter than the Sun (5,778 K)
Estimated Age
11.48 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
1.255 R☉
Stellar Mass
0.858 M☉
Metallicity [Fe/H]
-0.54
Extended Stellar Properties
Surface gravity (log g)
4.547 dex
Stellar density
0.440 g/cm³
Metallicity ratio
[M/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
1.099 mas
Total Proper Motion
22.085 mas/yr
PM Right Ascension
-9.91 mas/yr
PM Declination
-19.73 mas/yr
Galactic Cartesian (pc)
x = 0.293 · y = -0.686 · z = 0.666
Equatorial (J2000)
RA 293.15077° · Dec 41.72915°
Galactic ℓ, b
74.586° · 10.652°
Ecliptic λ, β
308.805° · 62.085°
HTM-20 index
-184720875
Similar Worlds
Kepler-1213 b
Rocky Terrestrial · F-type yellow-white
Radius 1.19 R⊕ · 2,634.7 ly
Kepler-1276 b
Rocky Terrestrial · F-type yellow-white
Radius 1.19 R⊕ · 1,756.3 ly
Kepler-1473 b
Rocky Terrestrial · F-type yellow-white
Radius 1.19 R⊕ · 2,127.4 ly
KOI-351 c
Rocky Terrestrial · F-type yellow-white
Radius 1.19 R⊕ · 2,766.6 ly
Kepler-380 b
Rocky Terrestrial · F-type yellow-white
Radius 1.19 R⊕ · 2,654.0 ly
Kepler-1617 b
Rocky Terrestrial · F-type yellow-white
Radius 1.20 R⊕ · 2,929.9 ly