TOI-1842 b
Astrophysical Synthesis & Habitability Characterization
TOI-1842 b is a confirmed gas giant exoplanet orbiting the star TOI-1842, located approximately 728.8 light-years (223.47 parsecs) from the Solar System. First announced in 2021 by Transiting Exoplanet Survey Satellite (TESS) using the Transit detection technique (producing an estimated primary transit depth of 0.3104% across the stellar disk), this world measures 12.349 Earth radii (1.1 Jupiter radii) and has a measured mass of 89.4 Earth masses (0.28 Jupiter masses). Combining its mass and radius yields a mean bulk density of 0.26 g/cm³ (a low bulk density dominated by an extended hydrogen-helium gaseous envelope), a surface gravity of 0.59 g⊕ (5.79 m/s²), and an escape velocity of 30.1 km/s.
In its orbital architecture around TOI-1842, TOI-1842 b completes one full revolution every 9.574 Earth days at a semi-major axis of 0.1 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 113.6 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.276, swinging from 0.0724 AU at periapsis out to 0.1276 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 1200 K (+927°C / +1701°F) and receiving 354.64 S⊕ (~482,664 W/m²), TOI-1842 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star TOI-1842 is classified as a stellar host with an effective photospheric temperature of 6,039 K, a radius of 2.032 R☉, a mass of 1.4643 M☉, an estimated bolometric luminosity of 4.927 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.5 Gyr and a metallicity of [Fe/H] = 0.332 dex (metal-rich relative to the Sun). From Earth, TOI-1842 shines at apparent V-band magnitude 9.815 (accessible to binoculars and small amateur telescopes) in the Northern 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-1842 |
| Spectral Type | Unclassified |
| Effective Temp (Teff) | 6,039 K |
| Stellar Radius | 2.0320 R☉ |
| Stellar Mass | 1.4643 M☉ |
| Bolometric Luminosity | 4.927 L☉ |
| Metallicity [Fe/H] | 0.332 dex |
| Stellar Age | 2.500 Gyr |
| Apparent Magnitude | V: 9.815 · G: 9.660 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.100000 AU |
| Orbital Period | 9.574 days |
| Mean Orbital Velocity | 113.6 km/s |
| Orbital Eccentricity (e) | 0.27600 |
| Orbital Inclination (i) | 88.4000° |
| Mean Bulk Density | 0.26 g/cm³ (30.1 km/s vesc) |
| Insolation Flux | 354.6390 S⊕ (~482,664 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 728.800 LY (223.465 pc) |