Key parameters at a glance
- A radius of 12.55 Earth radii
- A mass of 953.49 Earth masses
- Surface gravity around 6.05 g
- An orbital period of 3.123 days
- Semi-major axis 0.0384 AU
- Equilibrium temperature 1,001 K (728 °C)
- Distance from Earth 638.60 light-years
- Earth Similarity Index 0.168
- Travel time at Voyager 1 speed 11,261,660 years
- Almost certainly tidally locked to its host star given the close orbit
TOI-2989 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#1227of 1771
top 69.2%
This planet
12.55R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | TOI-2989 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 12.55 | 11.21 |
| Mass (M⊕) | 1.00 | 953.49 | 317.83 |
| Density (g/cm³) | 5.51 | 2.70 | 1.33 |
| Surface Gravity (g) | 1.00 | 6.05 | 2.53 |
| Insolation (S⊕) | 1.00 | 124.00 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 953.485 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 97825640
Gaia DR2
Gaia DR2 3531594209836279168
Gaia DR3
Gaia DR3 3531594209836279168
System
TOI-2989
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 3.12 Earth days (0.9% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0384 AU.
Transit Fingerprint
Depth
2.806 %
Duration
2.680 h
Impact parameter b
0.360
Rp / R★
0.152000
Transit midpoint (BJD)
2,459,302.2242
Photometric dip
Transit produces a flux drop of 28,060 ppm lasting ≈ 2.68 h.
Extended Orbital Architecture
Planet / star radius ratio
0.152000
Impact parameter (b)
0.360
RV semi-amplitude (K)
503.000 m/s
Transit mid-time (BJD)
2,459,302.2242
Angular separation (arcsec)
0.19600
Eq. Temperature
1,001K
(728 °C)
Insolation (S⊕)
124.00
Earth = 1.00
Earth Similarity (ESI)
0.168
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.
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
Frensch et al. 2025Instrument
TESS CCD Array
Publication
2025-06
Observation locale
Space
Discovery cohort
Planets confirmed in 2025 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-2989
Spectral Class
K-type orange
Effective Temperature
4,672 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.760 R☉
Stellar Mass
0.770 M☉
Metallicity [Fe/H]
-0.04
Extended Stellar Properties
Surface gravity (log g)
4.580 dex
Stellar density
2.538 g/cm³
Systemic radial velocity
-9.68 km/s
Rotational v·sin i
2.00 km/s
Rotation period
30.00 days
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
5.079 mas
Total Proper Motion
119.112 mas/yr
PM Right Ascension
-118.09 mas/yr
PM Declination
-15.54 mas/yr
Galactic Cartesian (pc)
x = -0.880 · y = 0.136 · z = -0.455
Equatorial (J2000)
RA 171.23168° · Dec -27.06236°
Galactic ℓ, b
280.173° · 31.958°
Ecliptic λ, β
183.664° · -28.126°
HTM-20 index
1701159928
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