WASP-76 b
Reference data for WASP-76 b: 1.85 Jupiter radii, 1.81-day orbit in Pisces, ESPRESSO iron-condensation asymmetry, and glory effect studies.
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 | 634 ly | ± 12 ly | Gaia DR3 trigonometric parallax of host star | definitive | ESA Gaia Archive — Data Release 3 |
| Orbital Period | 1.809886 d | ± 0.000001 d | Multi-epoch transit or astrometric orbital fitting | definitive | NASA Exoplanet Archive |
| Semi-Major Axis | 0.033 AU | ± 0.0007 AU | Keplerian third-law solution from stellar mass and orbital period | definitive | NASA Exoplanet Archive |
| Planetary Mass | 284.1 M⊕ | ± 9.5 M⊕ | Equivalent to 0.894 ± 0.030 Jupiter masses. | definitive | NASA Exoplanet Archive |
| Planetary Radius | 20.78 R⊕ | ± 0.45 R⊕ | Equivalent to 1.854 ± 0.040 Jupiter radii. | definitive | NASA Exoplanet Archive |
| Equilibrium Temperature | 2228 K | ± 35 K | Radiative equilibrium calculation from bolometric stellar insolation | definitive | NASA Exoplanet Archive |
J2000 Equatorial Sky Chart & Culmination Altitude
The chart below plots WASP-76 b — Molten-Iron-Rain Ultra-Hot Jupiter at RA 01h 46m 31.86s, Dec +02° 42′ 02.1″ within Pisces, 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
Discovered in 2013 by the Wide Angle Search for Planets (WASP) consortium, WASP-76 b orbits a bright F7V star in Pisces every 1.810 days at a separation of just 0.033 astronomical units. Although it contains slightly less mass than Jupiter (0.894 Jupiter masses), intense stellar irradiation heats its atmosphere above 2,200 K and inflates its radius to 1.854 Jupiter radii, resulting in an ultra-low bulk density near 0.18 grams per cubic centimeter.
In 2020, high-resolution transmission spectroscopy with the ESPRESSO instrument on the Very Large Telescope uncovered a striking chemical asymmetry between the planet's two terminators. As the evening limb enters the transit chord, strong neutral iron vapor absorption appears, blueshifted by 11 kilometers per second through day-to-night winds and planetary rotation. By the time the morning limb exits the transit, atomic iron absorption has vanished—demonstrating that vaporized iron condenses into liquid droplets on the cooler (~1,500 K) nightside and rains out below the observable cloud deck.
Rossiter-McLaughlin observations reveal that WASP-76 b travels in a nearly polar orbit tilted by roughly 61 degrees relative to its host star's equator. High-precision optical phase curves from CHEOPS and TESS also detected an asymmetric brightening near secondary eclipse, interpreted as a potential 'glory' scattering phenomenon from uniform spherical condensate droplets in the eastern atmosphere.
Practical Visual Observing Guide
- Host star WASP-76 (BD+01 316) shines at V = 9.52 in Pisces, accessible to small amateur telescopes.
- Produces a 1.15% (~0.013 mag) transit lasting 3.69 hours every 1.810 days, suitable for backyard CCD photometry.
- Features a wide stellar companion separated by 0.44 arcseconds that slightly dilutes raw photometric light curves.
Catalog Cross-Identifications & Aliases
Common Aliases: WASP-76b · BD+01 316 b · TIC 293481557 b
| Catalog Authority | Identifier |
|---|---|
| NASAEXOPLANET | WASP-76 b |
| SIMBAD | WASP-76 b |
Related Objects, Comparisons & Guides
HD 209458 b (Osiris First Transiting Planet)
Coordinates, Gaia DR3 distance (48.3 pc), 3.5247-day transit period, 1.359 R♃ inflated radius, and atmospheric escape data for HD 209458 b.
HD 189733 b — Cobalt-Blue Hot Jupiter Data
Reference profile for HD 189733 b: 2.22-day orbit, 2.4% transit depth in Vulpecula, atmospheric silicate clouds, and JWST H2S detection.
WASP-107 b — Super-Puff Exoplanet Profile
Reference data for WASP-107 b: 0.94 Jupiter radii at 30.5 Earth masses, 5.72-day orbit in Virgo, JWST internal heat and silicate cloud findings.
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.
Proper Motion, Radial Velocity & Redshift
How astronomers combine tangential proper motion (mas/yr), Doppler radial velocity (km/s), and cosmological redshift (z) to reconstruct 3D space motion.
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