Confirmed Exoplanet Discovered 2010

WASP-33 b

A gas giant orbiting the a-type white WASP-33, located approximately 397.7 light-years from Earth.

Key parameters at a glance

  • A radius of 17.86 Earth radii
  • A mass of 665.22 Earth masses
  • Surface gravity around 2.09 g
  • An orbital period of 1.220 days
  • Semi-major axis 0.0239 AU
  • Equilibrium temperature 2,782 K (2509 °C)
  • Distance from Earth 397.73 light-years
  • Earth Similarity Index 0.038
  • Travel time at Voyager 1 speed 7,013,927 years

WASP-33 b Planet Profile

Physical Specs

Radius
17.86 R⊕
Radius (Jupiter)
1.593 R♃
Mass
665.22 M⊕
Mass (Jupiter)
2.093 M♃
Density
0.69 g/cm³
Surface Gravity
2.09 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.038
HZ Position Inner
Controversial No

Discovery

Year 2010
Method Transit
Facility SuperWASP
Telescope Canon 200mm f/1.8L

Size rank in cohort

Rank by radius

#81of 1771

top 4.5%

This planet

17.86R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

Metric Earth WASP-33 b Jupiter
Radius (R⊕)1.0017.8611.21
Mass (M⊕)1.00665.22317.83
Density (g/cm³)5.510.691.33
Surface Gravity (g)1.002.092.53
Insolation (S⊕)1.009,392.050.037

Alternative Mass Estimates

Method Value Interpretation
Best measured mass 665.218 M⊕ Direct mass measurement (not derived).

Star Catalogue Identifiers

HD

HD 15082

HIP

HIP 11397

TIC

TIC 129979528

Gaia DR2

Gaia DR2 328636019723252096

Gaia DR3

Gaia DR3 328636019723252096

System

WASP-33

Percentile among Gas Giant cohort

Radius 17.856 R⊕ · percentile 95 / cohort 1771
Mass 665.218 M⊕ · percentile 56 / cohort 1747
Orbital period 1.22 d · percentile 1 / cohort 1533
Distance 121.94 pc · percentile 39 / cohort 1759
ESI 0.038 · percentile 1 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period
1.220 days
Semi-major axis
0.0239 AU
Eccentricity
0.000
Inclination
86.63 °

Year Length

A year here lasts approximately 1.22 Earth days (0.3% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0239 AU.

Transit Fingerprint

Depth

1.216 %

Duration

2.854 h

Impact parameter b

0.210

Rp / R★

0.111800

Transit midpoint (BJD)

2,459,883.1988

Photometric dip

Transit produces a flux drop of 12,160 ppm lasting ≈ 2.85 h.

Extended Orbital Architecture

Planet / star radius ratio

0.111800

Semi-major axis / stellar radius

3.571

Impact parameter (b)

0.210

RV semi-amplitude (K)

304.000 m/s

Transit mid-time (BJD)

2,459,883.1988

Sky-projected obliquity (λ)

251.20°

True obliquity (ψ)

108.19°

Angular separation (arcsec)

0.19600

Eq. Temperature

2,782K

(2509 °C)

Insolation (S⊕)

9,392.05

Earth = 1.00

Earth Similarity (ESI)

0.038

0 = alien, 1 = Earth-identical

Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.

Detection Signatures

Transit photometry

A transit dip has been observed from at least one telescope.

Radial velocity

Stellar wobble has been measured spectroscopically.

Orbital-brightness modulation

Host star brightness varies with the planet's orbit.

Discovery Paper

Instrument

iKon-L CCD Camera

Publication

2010-09

Observation locale

Ground

Host System: WASP-33

Spectral Class

A-type white

Effective Temperature

7,430 K — hotter than the Sun (5,778 K)

Estimated Age

Stellar Radius

1.444 R☉

Stellar Mass

1.495 M☉

Metallicity [Fe/H]

0.10

Extended Stellar Properties

Surface gravity (log g)

4.250 dex

Stellar density

0.700 g/cm³

Rotational v·sin i

85.60 km/s

Metallicity ratio

[M/H]

Distance
121.94 parsec
Light-years 397.73 ly
V-band magnitude
8.14 mag
Voyager-speed travel 7,013,927 yr

Multi-band Host Photometry — 11 bands

7.38.48.41B8.14V8.07Gaia7.88TESS7.58J7.52H7.47K7.38W17.44W27.47W37.25W4

Astrometric Data

Parallax

8.172 mas

Total Proper Motion

9.030 mas/yr

PM Right Ascension

-0.98 mas/yr

PM Declination

-8.98 mas/yr

Galactic Cartesian (pc)

x = 0.636 · y = 0.474 · z = 0.609

Equatorial (J2000)

RA 36.71274° · Dec 37.55044°

Galactic ℓ, b

143.097° · -21.557°

Ecliptic λ, β

46.816° · 21.755°

HTM-20 index

533196778

Observation Record

Photometric series

1

RV measurements

1

Transmission spectra

1

Emission spectra

11

Archive notes

3

Similar Worlds

Explore Related Categories