Kepler-49 c
Astrophysical Synthesis & Habitability Characterization
Kepler-49 c is a confirmed sub-neptune exoplanet orbiting the star Kepler-49, located approximately 1015.1 light-years (311.22 parsecs) from the Solar System. First announced in 2012 by Kepler using the Transit detection technique (producing an estimated primary transit depth of 0.1315% across the stellar disk), this world measures 2.444 Earth radii and has a measured mass of 8.38 Earth masses. Combining its mass and radius yields a mean bulk density of 3.17 g/cm³ (an intermediate density indicative of a deep water-ice mantle or dense volatile envelope), a surface gravity of 1.4 g⊕ (13.73 m/s²), and an escape velocity of 20.7 km/s.
In its orbital architecture around Kepler-49, Kepler-49 c completes one full revolution every 10.91 Earth days at a semi-major axis of 0.07821 AU (orbiting interior to Mercury's 0.387 AU benchmark in the Solar System). Its mean orbital velocity is approximately 78 km/s (compared to Earth's 29.8 km/s). With a near-circular eccentricity of e = 0.008 (ranging from 0.0776 AU at periapsis to 0.0788 AU at apoapsis), the planet experiences minimal orbital distance variation.
⚠️ Thermal Regime (Irradiated / Hot Zone): At an equilibrium temperature of 443 K (+170°C / +338°F) and receiving 12.34 S⊕ (~16,796 W/m²), Kepler-49 c orbits interior to the runaway greenhouse boundary where surface liquid water cannot persist.
The host star Kepler-49 is classified as a low-mass red dwarf of spectral type M1 V with an effective photospheric temperature of 4,096 K, a radius of 0.618 R☉, a mass of 0.607 M☉, an estimated bolometric luminosity of 0.096 L☉. Stellar evolution modeling indicates an estimated stellar age of 2.88 Gyr and a metallicity of [Fe/H] = 0.03 dex (near-solar heavy-element abundance). From Earth, Kepler-49 shines at apparent V-band magnitude 15.655 (faint and requiring research-grade or CCD telescopic photometry) in the Northern celestial hemisphere. The Kepler-49 system is a multi-planet architecture hosting 4 confirmed worlds, with Kepler-49 c sharing its stellar neighborhood alongside Kepler-49 d, Kepler-49 b, Kepler-49 e.
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: Kepler · Catalogue Source: NASA Exoplanet Archive (IPAC / Caltech).
☀️ Host Star Telemetry
| Host Star Name | Kepler-49 |
| Spectral Type | M1 V |
| Effective Temp (Teff) | 4,096 K |
| Stellar Radius | 0.6180 R☉ |
| Stellar Mass | 0.6070 M☉ |
| Bolometric Luminosity | 0.096 L☉ |
| Metallicity [Fe/H] | 0.030 dex |
| Stellar Age | 2.880 Gyr |
| Apparent Magnitude | V: 15.655 · G: 15.229 |
| System Architecture | 1 Star, 4 Planets |
🪐 Orbital & Physical Dynamics
| Semi-Major Axis (a) | 0.078210 AU |
| Orbital Period | 10.91 days |
| Mean Orbital Velocity | 78 km/s |
| Orbital Eccentricity (e) | 0.00800 |
| Orbital Inclination (i) | 88.6800° |
| Mean Bulk Density | 3.17 g/cm³ (20.7 km/s vesc) |
| Insolation Flux | 12.3410 S⊕ (~16,796 W/m²) |
| Habitable Zone Status | Exterior / Non-HZ |
| Celestial Distance | 1015.100 LY (311.222 pc) |