TOI-2589 b
Astrophysical Synthesis & Habitability Characterization
TOI-2589 b is a confirmed gas giant exoplanet orbiting the star TOI-2589, located approximately 653.2 light-years (200.27 parsecs) from the Solar System. First announced in 2023 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 1.0759% across the stellar disk), this world measures 12.106 Earth radii (1.08 Jupiter radii) and has a measured mass of 1112.399 Earth masses (3.5 Jupiter masses). Combining its mass and radius yields a mean bulk density of 3.46 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 7.59 g⊕ (74.43 m/s²), and an escape velocity of 107.2 km/s.
In its orbital architecture around TOI-2589, TOI-2589 b completes one full revolution every 61.628 Earth days at a semi-major axis of 0.3 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 53 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.522, swinging from 0.1434 AU at periapsis out to 0.4566 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 592 K (+319°C / +606°F) and receiving 21.75 S⊕ (~29,597 W/m²), TOI-2589 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-2589 is classified as a stellar host with an effective photospheric temperature of 5,579 K, a radius of 1.07 R☉, a mass of 0.93 M☉, an estimated bolometric luminosity of 0.995 L☉. Stellar evolution modeling indicates an estimated stellar age of 11 Gyr and a metallicity of [Fe/H] = 0.12 dex (metal-rich relative to the Sun). From Earth, TOI-2589 shines at apparent V-band magnitude 11.415 (faint and requiring research-grade or CCD telescopic photometry) in the Southern celestial hemisphere.
Methodology: Computed using the Schulze-Makuch et al. (2011) weighted metric comparing physical interior (radius, estimated density) and surface thermal regime (escape velocity, equilibrium temperature).
Discovery Facility: Transiting Exoplanet Survey Satellite (TESS) · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | TOI-2589 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 5,579 K |
| Stellar Radius | 1.0700 R☉ |
| Stellar Mass | 0.9300 M☉ |
| Bolometric Luminosity | 0.995 L☉ |
| Metallicity [Fe/H] | 0.120 dex |
| Stellar Age | 11.000 Gyr |
| Apparent Magnitude | V: 11.415 · G: 11.196 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.300000 AU |
| Orbital Period | 61.628 days |
| Mean Orbital Velocity | 53 km/s |
| Orbital Eccentricity (e) | 0.52200 |
| Orbital Inclination (i) | 89.1700° |
| Mean Bulk Density | 3.46 g/cm³ (107.2 km/s vesc) |
| Insolation Flux | 21.7464 S⊕ (~29,597 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 653.200 LY (200.273 pc) |