Key parameters at a glance
- A radius of 2.56 Earth radii
- A mass of 32.00 Earth masses
- Surface gravity around 4.88 g
- An orbital period of 8.953 days
- Semi-major axis 0.0799 AU
- Equilibrium temperature 714 K (441 °C)
- Distance from Earth 308.67 light-years
- Earth Similarity Index 0.331
- Travel time at Voyager 1 speed 5,443,323 years
- Almost certainly tidally locked to its host star given the close orbit
TOI-1174 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1090of 1978
top 55.1%
This planet
2.56R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-1174 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.56 | 11.21 |
| Mass (M⊕) | 1.00 | 32.00 | 317.83 |
| Density (g/cm³) | 5.51 | 11.00 | 1.33 |
| Surface Gravity (g) | 1.00 | 4.88 | 2.53 |
| Insolation (S⊕) | 1.00 | 52.02 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 32.000 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 154089169
Gaia DR2
Gaia DR2 1674293361400214272
Gaia DR3
Gaia DR3 1674293361400214272
System
TOI-1174
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 8.95 Earth days (2.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0799 AU.
Transit Fingerprint
Depth
0.114 %
Duration
3.063 h
Impact parameter b
0.383
Rp / R★
0.030560
Transit midpoint (BJD)
2,459,657.0330
Photometric dip
Transit produces a flux drop of 1,136 ppm lasting ≈ 3.06 h.
Extended Orbital Architecture
Planet / star radius ratio
0.030560
Impact parameter (b)
0.383
Transit mid-time (BJD)
2,459,657.0330
Long. of periastron (ω)
90.00°
Angular separation (arcsec)
0.84500
Eq. Temperature
714K
(441 °C)
Insolation (S⊕)
52.02
Earth = 1.00
Earth Similarity (ESI)
0.331
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. Close-orbiting tidally-locked around a cool host.
Discovery Paper
Primary reference
Polanski et al. 2024Instrument
TESS CCD Array
Publication
2024-06
Observation locale
Space
Discovery cohort
Planets confirmed in 2024 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-1174
Spectral Class
K-type orange
Effective Temperature
5,030 K — cooler than the Sun (5,778 K)
Estimated Age
2.70 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.760 R☉
Stellar Mass
0.850 M☉
Metallicity [Fe/H]
0.00
Extended Stellar Properties
Surface gravity (log g)
4.573 dex
Stellar density
2.437 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
10.538 mas
Total Proper Motion
92.970 mas/yr
PM Right Ascension
-81.08 mas/yr
PM Declination
45.50 mas/yr
Galactic Cartesian (pc)
x = -0.318 · y = -0.178 · z = 0.931
Equatorial (J2000)
RA 209.21718° · Dec 68.61821°
Galactic ℓ, b
114.209° · 47.387°
Ecliptic λ, β
146.935° · 67.687°
HTM-20 index
905800916
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