Key parameters at a glance
- A radius of 1.74 Earth radii
- A mass of 3.68 Earth masses
- Surface gravity around 1.22 g
- An orbital period of 32.509 days
- Semi-major axis 0.1513 AU
- Equilibrium temperature 288 K (15 °C)
- Distance from Earth 117.45 light-years
- Earth Similarity Index 0.875
- Travel time at Voyager 1 speed 2,071,313 years
- Almost certainly tidally locked to its host star given the close orbit
2 siblings around TOI-1266
TOI-1266 d shares its host star with 2 other confirmed planets. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| TOI-1266 b | Sub-Neptune | 2.52 | 4.46 | 10.895 | 415 | 2020 |
| TOI-1266 c | Super-Earth | 1.98 | 3.17 | 18.803 | 346 | 2020 |
| TOI-1266 d this | Super-Earth | 1.74 | 3.68 | 32.509 | 288 | 2025 |
TOI-1266 d Planet Profile
Physical Specs
Classification
Planet Type
Super-Earth
Discovery
Size rank in cohort
Rank by radius
#344of 1176
top 29.2%
This planet
1.74R⊕
Super-Earth median
1.60R⊕
Nearest-size peers
| Metric | Earth | TOI-1266 d | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 1.74 | 11.21 |
| Mass (M⊕) | 1.00 | 3.68 | 317.83 |
| Density (g/cm³) | 5.51 | 3.84 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.22 | 2.53 |
| Insolation (S⊕) | 1.00 | 1.30 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 3.680 M⊕ | Direct mass measurement (not derived). |
| Minimum mass (M sin i) | 4.590 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
TIC
TIC 467179528
Gaia DR2
Gaia DR2 1678074272650459008
Gaia DR3
Gaia DR3 1678074272650459008
System
TOI-1266
Percentile among Super-Earth cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 32.51 Earth days (8.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1513 AU.
Extended Orbital Architecture
Semi-major axis / stellar radius
73.980
RV semi-amplitude (K)
1.630 m/s
Transit mid-time (BJD)
2,458,729.0300
Angular separation (arcsec)
4.20000
Eq. Temperature
288K
(15 °C)
Insolation (S⊕)
1.30
Earth = 1.00
Earth Similarity (ESI)
0.875
0 = alien, 1 = Earth-identical
Within the conservative habitable zone — liquid water is physically possible with adequate atmospheric pressure. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Greklek Mckeon et al. 2024Instrument
TESS CCD Array
Publication
2024-09
Observation locale
Space
Discovery cohort
Planets confirmed in 2025 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-1266
Spectral Class
M-type red dwarf
Effective Temperature
3,563 K — cooler than the Sun (5,778 K)
Estimated Age
4.60 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.423 R☉
Stellar Mass
0.437 M☉
Metallicity [Fe/H]
-0.11
Extended Stellar Properties
Surface gravity (log g)
4.826 dex
Stellar density
8.130 g/cm³
Systemic radial velocity
-41.58 km/s
Rotational v·sin i
1.30 km/s
Rotation period
44.60 days
Activity index (log R'HK)
-5.500
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
27.740 mas
Total Proper Motion
152.773 mas/yr
PM Right Ascension
-150.65 mas/yr
PM Declination
-25.37 mas/yr
Galactic Cartesian (pc)
x = -0.389 · y = -0.126 · z = 0.912
Equatorial (J2000)
RA 197.99658° · Dec 65.83370°
Galactic ℓ, b
119.581° · 51.161°
Ecliptic λ, β
147.620° · 62.547°
HTM-20 index
-1935697101
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