Kepler-452 b
Reference profile for Kepler-452 b: 384.8-day orbit, 1.05 AU separation from a G2V star, 1.63 Earth radii, and validation status.
Provenance-Backed Scientific Measurements
Every measurement below preserves its unit, uncertainty interval, observational method, reference epoch, quality status, and primary catalog source. See Uncertainty & Provenance for how competing measurements are handled.
| Parameter | Value | Uncertainty | Method & Epoch | Quality Status | Source Archive |
|---|---|---|---|---|---|
| Distance | 1799 ly | ± 28 ly | Gaia DR3 astrometric parallax of host star Kepler-452. | definitive | ESA Gaia Archive — Data Release 3 |
| Orbital Period | 384.843 d | ± 0.01 d | Multi-epoch transit or astrometric orbital fitting | high-confidence | NASA Exoplanet Archive |
| Semi-Major Axis | 1.046 AU | ± 0.017 AU | Keplerian third-law solution from stellar mass and orbital period | high-confidence | NASA Exoplanet Archive |
| Planetary Radius | 1.63 R⊕ | ± 0.21 R⊕ | Transit depth photometry combined with Gaia stellar radius | high-confidence | NASA Exoplanet Archive |
| Estimated Mass | 3.29 M⊕ | ± 1.1 M⊕ | Probabilistic mass-radius forecast; spans rocky super-Earth to volatile-rich mini-Neptune. | model-dependent | NASA Exoplanet Archive |
| Equilibrium Temperature | 265 K | ± 14 K | Radiative equilibrium calculation from bolometric stellar insolation | high-confidence | NASA Exoplanet Archive |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots Kepler-452 b — Super-Earth Around a G2 Star at RA 19h 44m 00.89s, Dec +44° 16′ 39.2″ within Cygnus, alongside peak meridian transit altitudes for 40°N and 30°S observers. Use the RA/Dec Coordinate Converter to compute exact culmination altitude for your latitude.
Astrophysical Context & Structure
Announced by the Kepler mission team in July 2015, Kepler-452 b drew immediate attention as the first near-Earth-sized world identified in the habitable zone of a G2V star closely resembling the Sun. The host star, located roughly 1,799 light-years away in Cygnus, possesses the same effective temperature as the Sun (5,757 K) and a mass 3.7 percent greater, but an evolutionary age near 6 billion years makes it about 1.5 billion years older and 20 percent more luminous.
Completing an orbit every 384.84 days at 1.046 astronomical units, the planet intercepts roughly 10 percent more incident stellar energy than modern Earth. Its measured radius of 1.63 ± 0.21 Earth radii places it right across the Fulton radius valley, meaning that depending on where the true radius falls within its uncertainty interval, the world has roughly an equal probability of being a dense rocky super-Earth or a volatile-shrouded mini-Neptune.
Because a 385-day period permitted only four transit events during Kepler's four-year primary mission—each producing a shallow 200-parts-per-million dip—confirming the signal required exhaustive statistical validation. Subsequent re-analyses of instrumental systematic noise in long-cadence Kepler light curves have debated the signal-to-noise threshold of three- and four-transit candidates, making Kepler-452 b a classic case study in long-period transit detection limits.
Practical Visual Observing Guide
- Host star Kepler-452 shines at magnitude V ~ 13.42 in Cygnus, visible visually in 10-inch and larger amateur telescopes.
- The 10.5-hour transit produces only a 0.02% brightness drop, undetectable from the ground.
- Radial velocity reflex motion is estimated near 0.3 m/s, requiring next-generation extreme-precision spectrographs.
Catalog Cross-Identifications & Aliases
Common Aliases: Kepler-452b · KOI-7016.01 · KIC 8311864 b
| Catalog Authority | Identifier |
|---|---|
| NASAEXOPLANET | Kepler-452 b |
| SIMBAD | Kepler-452 b |
Related Objects, Comparisons & Guides
Kepler-186 f — First Earth-Size Habitable World
Reference data for Kepler-186 f: 1.17 Earth radii, 129.9-day habitable-zone orbit around an M1 dwarf in Cygnus, and insolation metrics.
Kepler-16 b — Circumbinary Saturn-Mass Planet
Reference data for Kepler-16 b: Saturn mass and radius, 228.8-day circumbinary orbit around an eclipsing binary in Cygnus, and discovery metrics.
51 Pegasi b (Dimidium First Hot Jupiter)
Coordinates, Gaia DR3 distance (15.46 pc), 4.2308-day orbital period, Nobel-winning radial-velocity discovery, and observing guide for 51 Pegasi b.
Exoplanet Transit & Radial Velocity Methods
How astronomers detect and characterize exoplanets using photometric transit depth ((Rp/R*)²), Doppler radial velocity (M sin i), and JWST transmission spectra.
Measurement Uncertainty & Optics in Astronomy
How random vs systematic errors, asymmetric error bars, model dependencies, and optical aperture/exit-pupil limits shape astronomical measurements.
Scientific Sources & Dataset Provenance
- NASA Exoplanet Archive (2026-10-01 snapshot): Akeson, R. L., et al. 2013, PASP, 125, 989; NASA Exoplanet Archive (IPAC/Caltech) — NASA Exoplanet Science Institute (NExScI / Caltech / IPAC)
- ESA Gaia Archive — Data Release 3 (DR3 (2022-06-13)): Gaia Collaboration, Vallenari, A., et al. 2023, A&A, 674, A1 (Gaia Data Release 3) — European Space Agency / Gaia DPAC