HIP 55507 b
Astrophysical Synthesis & Habitability Characterization
HIP 55507 b is a confirmed gas giant exoplanet orbiting the star HIP 55507, located approximately 83.1 light-years (25.49 parsecs) from the Solar System. First announced in 2022 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.6 Earth radii (1.12 Jupiter radii) and has a measured mass of 2585.534 Earth masses (8.13 Jupiter masses). Combining its mass and radius yields a mean bulk density of 7.13 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 16.29 g⊕ (159.75 m/s²), and an escape velocity of 160.2 km/s.
In its orbital architecture around HIP 55507, HIP 55507 b completes one full revolution every 5138.437 Earth days (14.07Julian years) at a semi-major axis of 5.062 AU (corresponding to the middle-system regime between Mars at 1.52 AU and Jupiter at 5.20 AU). Its mean orbital velocity is approximately 10.7 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.362, swinging from 3.2296 AU at periapsis out to 6.8944 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
❄️ Thermal Regime (Cryogenic Zone): With an equilibrium temperature of 76 K (-197°C / -323°F) and an incident flux of 0.01 S⊕ (~8 W/m²), surface water and volatile species on HIP 55507 b would remain locked in cryogenic ice phases unless warmed by subsurface tidal or radiogenic heating.
The host star HIP 55507 is classified as a low-mass red dwarf of spectral type M0 with an effective photospheric temperature of 4,171 K, a radius of 0.7236 R☉, a mass of 0.65 M☉, an estimated bolometric luminosity of 0.142 L☉. From Earth, HIP 55507 shines at apparent V-band magnitude 9.8 (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: Multiple Observatories · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | HIP 55507 |
| Spectral Type | M0 |
| Effective Temp (Teff) | 4,171 K |
| Stellar Radius | 0.7236 R☉ |
| Stellar Mass | 0.6500 M☉ |
| Bolometric Luminosity | 0.142 L☉ |
| Metallicity [Fe/H] | — |
| Stellar Age | — |
| Apparent Magnitude | V: 9.800 · G: 9.268 |
| System Architecture | 1 Star, 1 Planet |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 5.062000 AU |
| Orbital Period | 5138.437 days |
| Mean Orbital Velocity | 10.7 km/s |
| Orbital Eccentricity (e) | 0.36200 |
| Orbital Inclination (i) | 135.0220° |
| Mean Bulk Density | 7.13 g/cm³ (160.2 km/s vesc) |
| Insolation Flux | 0.0056 S⊕ (~8 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 83.100 LY (25.489 pc) |