ups And c
Astrophysical Synthesis & Habitability Characterization
ups And c is a confirmed gas giant exoplanet orbiting the star ups And, located approximately 43.7 light-years (13.41 parsecs) from the Solar System. First announced in 1999 by Multiple Observatories using the Radial Velocity detection technique (measuring periodic Doppler reflex motion in the host star's spectrum), this world measures 12.3 Earth radii (1.1 Jupiter radii) and has a measured mass of 4443.241 Earth masses (13.98 Jupiter masses). Combining its mass and radius yields a mean bulk density of 13.17 g/cm³ (an iron-enriched, high-compression rocky core), a surface gravity of 29.37 g⊕ (288.02 m/s²), and an escape velocity of 212.6 km/s.
In its orbital architecture around ups And, ups And c completes one full revolution every 241.258 Earth days at a semi-major axis of 0.827774 AU (comparable to the inner terrestrial zone between Venus, Earth at 1.00 AU, and Mars at 1.52 AU). Its mean orbital velocity is approximately 37.3 km/s (compared to Earth's 29.8 km/s). The planet follows a highly eccentric trajectory (e = 0.2596, swinging from 0.6129 AU at periapsis out to 1.0427 AU at apoapsis), pointing to past dynamical scattering or secular gravitational perturbations.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 408 K (+135°C / +275°F) and receiving 4.89 S⊕ (~6,660 W/m²), ups And c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star ups And is classified as a warm F-type star of spectral type F8 V with an effective photospheric temperature of 6,157 K, a radius of 1.56 R☉, a mass of 1.3 M☉, an estimated bolometric luminosity of 3.138 L☉. Stellar evolution modeling indicates an estimated stellar age of 5 Gyr and a metallicity of [Fe/H] = 0.101 dex (metal-rich relative to the Sun). From Earth, ups And shines at apparent V-band magnitude 4.096 (visible to the unaided human eye under dark skies) in the Northern celestial hemisphere. The ups And system is a multi-planet architecture hosting 3 confirmed worlds, with ups And c sharing its stellar neighborhood alongside ups And b, ups And d.
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 | ups And |
| Spectral Type | F8 V |
| Effective Temp (Teff) | 6,157 K |
| Stellar Radius | 1.5600 R☉ |
| Stellar Mass | 1.3000 M☉ |
| Bolometric Luminosity | 3.138 L☉ |
| Metallicity [Fe/H] | 0.101 dex |
| Stellar Age | 5.000 Gyr |
| Apparent Magnitude | V: 4.096 · G: 3.987 |
| System Architecture | 2 Stars, 3 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.827774 AU |
| Orbital Period | 241.258 days |
| Mean Orbital Velocity | 37.3 km/s |
| Orbital Eccentricity (e) | 0.25960 |
| Orbital Inclination (i) | — |
| Mean Bulk Density | 13.17 g/cm³ (212.6 km/s vesc) |
| Insolation Flux | 4.8931 S⊕ (~6,660 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 43.700 LY (13.405 pc) |