Key parameters at a glance

A radius of 10.42 Earth radii
A mass of 317.83 Earth masses
Surface gravity around 2.92 g
An orbital period of 5.748 days
Semi-major axis 0.0628 AU
Equilibrium temperature 1,100 K (827 °C)
Distance from Earth 983.24 light-years
Earth Similarity Index 0.150
Travel time at Voyager 1 speed 17,339,373 years

WASP-129 b Planet Profile

Physical Specs

Radius

10.42 R⊕

Radius (Jupiter)

0.930 R♃

Mass

317.83 M⊕

Mass (Jupiter)

1.000 M♃

Density

1.60 g/cm³

Surface Gravity

2.92 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.150

HZ Position Inner

Controversial No

Discovery

Year 2016

Method Transit

Facility SuperWASP-South

Telescope Canon 200mm f/1.8L

Size rank in cohort

Rank by radius

#1734of 1771

top 97.9%

This planet

10.42R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

TOI-2373 b 10.42 R⊕ WASP-43 b 10.42 R⊕ TOI-5634 A b 10.42 R⊕

Metric	Earth	WASP-129 b	Jupiter
Radius (R⊕)	1.00	10.42	11.21
Mass (M⊕)	1.00	317.83	317.83
Density (g/cm³)	5.51	1.60	1.33
Surface Gravity (g)	1.00	2.92	2.53
Insolation (S⊕)	1.00	345.72	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	317.830 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 61538902

Gaia DR2

Gaia DR2 5380888758195682944

Gaia DR3

Gaia DR3 5380888758195682944

System

WASP-129

Percentile among Gas Giant cohort

Radius 10.424 R⊕ · percentile 2 / cohort 1771

Mass 317.830 M⊕ · percentile 35 / cohort 1747

Orbital period 5.75 d · percentile 39 / cohort 1533

Distance 301.46 pc · percentile 60 / cohort 1759

ESI 0.150 · percentile 36 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

5.748 days

Semi-major axis

0.0628 AU

Eccentricity

0.096

Inclination

87.70 °

Year Length

A year here lasts approximately 5.75 Earth days (1.6% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0628 AU.

Transit Fingerprint

Depth

1.226 %

Duration

2.686 h

Impact parameter b

0.620

Rp / R★

0.106800

Transit midpoint (BJD)

2,457,027.4373

Photometric dip

Transit produces a flux drop of 12,259 ppm lasting ≈ 2.69 h.

Extended Orbital Architecture

Planet / star radius ratio

0.106800

Semi-major axis / stellar radius

15.152

Impact parameter (b)

0.620

RV semi-amplitude (K)

110.000 m/s

Transit mid-time (BJD)

2,457,027.4373

Angular separation (arcsec)

0.20800

Eq. Temperature

1,100K

(827 °C)

Insolation (S⊕)

345.72

Earth = 1.00

Earth Similarity (ESI)

0.150

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.

Discovery Paper

Primary reference

Maxted et al. 2016

Instrument

iKon-L CCD Camera

Publication

2016-06

Observation locale

Ground

Discovery cohort

Planets confirmed in 2016 at SuperWASP-South (11 shown).

WASP-132 b · Gas Giant WASP-130 b · Neptune-like WASP-139 b · Neptune-like WASP-140 b · Gas Giant WASP-141 b · Gas Giant WASP-124 b · Gas Giant WASP-126 b · Gas Giant WASP-119 b · Gas Giant WASP-133 b · Gas Giant WASP-131 b · Gas Giant WASP-142 b · Gas Giant

Host System: WASP-129

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,900 K — hotter than the Sun (5,778 K)

Estimated Age

1.00 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

0.900 R☉

Stellar Mass

1.000 M☉

Metallicity [Fe/H]

0.15

Extended Stellar Properties

Surface gravity (log g)

4.530 dex

Stellar density

1.940 g/cm³

Systemic radial velocity

21.99 km/s

Rotational v·sin i

2.70 km/s

Metallicity ratio

[Fe/H]

Distance

301.46 parsec

Light-years 983.24 ly

V-band magnitude

12.18 mag

Voyager-speed travel 17,339,373 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

3.289 mas

Total Proper Motion

11.779 mas/yr

PM Right Ascension

11.67 mas/yr

PM Declination

-1.59 mas/yr

Galactic Cartesian (pc)

x = -0.741 · y = 0.048 · z = -0.670

Equatorial (J2000)

RA 176.29905° · Dec -42.06396°

Galactic ℓ, b

289.989° · 19.137°

Ecliptic λ, β

196.715° · -39.326°

HTM-20 index

-574668960