Key parameters at a glance
- A radius of 2.59 Earth radii
- A mass of 10.00 Earth masses
- Surface gravity around 1.50 g
- An orbital period of 3.945 days
- Semi-major axis 0.0480 AU
- Equilibrium temperature 1,125 K (852 °C)
- Distance from Earth 465.97 light-years
- Earth Similarity Index 0.226
- Travel time at Voyager 1 speed 8,217,368 years
TOI-669 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1054of 1978
top 53.2%
This planet
2.59R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-669 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.59 | 11.21 |
| Mass (M⊕) | 1.00 | 10.00 | 317.83 |
| Density (g/cm³) | 5.51 | 3.17 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.50 | 2.53 |
| Insolation (S⊕) | 1.00 | 388.20 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 10.000 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 124573851
Gaia DR2
Gaia DR2 3777506754255516800
Gaia DR3
Gaia DR3 3777506754255516800
System
TOI-669
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 3.95 Earth days (1.1% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0480 AU.
Transit Fingerprint
Depth
0.084 %
Duration
2.871 h
Impact parameter b
0.339
Rp / R★
0.023992
Transit midpoint (BJD)
2,458,546.1419
Photometric dip
Transit produces a flux drop of 841 ppm lasting ≈ 2.87 h.
Extended Orbital Architecture
Planet / star radius ratio
0.023992
Semi-major axis / stellar radius
10.300
Impact parameter (b)
0.339
RV semi-amplitude (K)
4.260 m/s
Transit mid-time (BJD)
2,458,546.1419
Long. of periastron (ω)
90.00°
Angular separation (arcsec)
0.33600
Eq. Temperature
1,125K
(852 °C)
Insolation (S⊕)
388.20
Earth = 1.00
Earth Similarity (ESI)
0.226
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.
Detection Signatures
Transit photometry
A transit dip has been observed from at least one telescope.
Radial velocity
Stellar wobble has been measured spectroscopically.
Discovery Paper
Primary reference
Akana Murphy et al. 2023Instrument
TESS CCD Array
Publication
2023-10
Observation locale
Space
Discovery cohort
Planets confirmed in 2023 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-669
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,597 K — cooler than the Sun (5,778 K)
Estimated Age
7.90 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.988 R☉
Stellar Mass
0.925 M☉
Metallicity [Fe/H]
0.00
Extended Stellar Properties
Surface gravity (log g)
4.412 dex
Stellar density
1.340 g/cm³
Activity index (log R'HK)
-5.010
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
6.971 mas
Total Proper Motion
72.749 mas/yr
PM Right Ascension
9.84 mas/yr
PM Declination
72.08 mas/yr
Galactic Cartesian (pc)
x = -0.929 · y = 0.359 · z = -0.090
Equatorial (J2000)
RA 158.90070° · Dec -5.18137°
Galactic ℓ, b
252.337° · 43.947°
Ecliptic λ, β
162.493° · -13.030°
HTM-20 index
1445414764
Similar Worlds
Kepler-604 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.59 R⊕ · 3,348.0 ly
Kepler-265 e
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.59 R⊕ · 4,175.6 ly
HD 109833 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.59 R⊕ · 259.5 ly
Kepler-843 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.59 R⊕ · 3,801.9 ly
Kepler-1886 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.58 R⊕ · 3,455.7 ly
Kepler-461 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.58 R⊕ · 2,257.5 ly