HIP 57274 b
Astrophysical Synthesis & Habitability Characterization
HIP 57274 b is a confirmed gas giant exoplanet orbiting the star HIP 57274, located approximately 84.3 light-years (25.86 parsecs) from the Solar System. First announced in 2011 by W. M. Keck Observatory using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world has a minimum or true mass of 3359.446 Earth masses (10.57 M♃), while its physical transit radius has not yet been geometrically observed.
In its orbital architecture around HIP 57274, HIP 57274 b completes one full revolution every 8.135 Earth days at a semi-major axis of 0.07 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 93.6 km/s (compared to Earth's 29.8 km/s). Its moderate orbital eccentricity of e = 0.19 carries the world between 0.0567 AU at periapsis and 0.0833 AU at apoapsis, driving measurable seasonal insolation cycles.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 726 K (+453°C / +847°F) and receiving 316.09 S⊕ (~430,192 W/m²), HIP 57274 b orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star HIP 57274 is classified as an orange K-type star of spectral type K4 V with an effective photospheric temperature of 4,510 K, a radius of 0.78 R☉, a mass of 0.29 M☉, an estimated bolometric luminosity of 0.226 L☉. Stellar evolution modeling indicates an estimated stellar age of 7.87 Gyr and a metallicity of [Fe/H] = 0.01 dex (near-solar heavy-element abundance). From Earth, HIP 57274 shines at apparent V-band magnitude 8.97 (accessible to binoculars and small amateur telescopes) in the Northern celestial hemisphere. The HIP 57274 system is a multi-planet architecture hosting 3 confirmed worlds, with HIP 57274 b sharing its stellar neighborhood alongside HIP 57274 c, HIP 57274 d.
Discovery Facility: W. M. Keck Observatory · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HIP 57274 |
| Spectral Type | K4 V |
| Effective Temp (Teff) | 4,510 K |
| Stellar Radius | 0.7800 R☉ |
| Stellar Mass | 0.2900 M☉ |
| Bolometric Luminosity | 0.226 L☉ |
| Metallicity [Fe/H] | 0.010 dex |
| Stellar Age | 7.870 Gyr |
| Apparent Magnitude | V: 8.970 · G: 8.571 |
| System Architecture | 1 Star, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.070000 AU |
| Orbital Period | 8.135 days |
| Mean Orbital Velocity | 93.6 km/s |
| Orbital Eccentricity (e) | 0.19000 |
| Orbital Inclination (i) | 0.1980° |
| Insolation Flux | 316.0850 S⊕ (~430,192 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 84.300 LY (25.862 pc) |