Key parameters at a glance

A radius of 15.24 Earth radii
A mass of 314.97 Earth masses
Surface gravity around 1.36 g
An orbital period of 1.333 days
Semi-major axis 0.0240 AU
Equilibrium temperature 1,855 K (1582 °C)
Distance from Earth 690.57 light-years
Earth Similarity Index 0.061
Travel time at Voyager 1 speed 12,178,203 years

WASP-149 b Planet Profile

Physical Specs

Radius

15.24 R⊕

Radius (Jupiter)

1.360 R♃

Mass

314.97 M⊕

Mass (Jupiter)

0.991 M♃

Density

0.49 g/cm³

Surface Gravity

1.36 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.061

HZ Position Inner

Controversial No

Discovery

Year 2025

Method Transit

Facility SuperWASP

Telescope Canon 200mm f/1.8L

Size rank in cohort

Rank by radius

#216of 1771

top 12.1%

This planet

15.24R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

TOI-1516 b 15.24 R⊕ TrES-2 b 15.24 R⊕ WASP-74 b 15.24 R⊕

Metric	Earth	WASP-149 b	Jupiter
Radius (R⊕)	1.00	15.24	11.21
Mass (M⊕)	1.00	314.97	317.83
Density (g/cm³)	5.51	0.49	1.33
Surface Gravity (g)	1.00	1.36	2.53
Insolation (S⊕)	1.00	1,966.00	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	314.968 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 19342878

System

WASP-149

Percentile among Gas Giant cohort

Radius 15.244 R⊕ · percentile 88 / cohort 1771

Mass 314.968 M⊕ · percentile 35 / cohort 1747

Orbital period 1.33 d · percentile 2 / cohort 1533

Distance 211.73 pc · percentile 52 / cohort 1759

ESI 0.061 · percentile 9 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

1.333 days

Semi-major axis

0.0240 AU

Eccentricity

0.000

Inclination

83.02 °

Year Length

A year here lasts approximately 1.33 Earth days (0.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0240 AU.

Transit Fingerprint

Depth

1.683 %

Duration

2.050 h

Impact parameter b

0.580

Rp / R★

0.129700

Transit midpoint (BJD)

2,457,757.6245

Photometric dip

Transit produces a flux drop of 16,834 ppm lasting ≈ 2.05 h.

Extended Orbital Architecture

Planet / star radius ratio

0.129700

Semi-major axis / stellar radius

4.800

Impact parameter (b)

0.580

RV semi-amplitude (K)

175.250 m/s

Transit mid-time (BJD)

2,457,757.6245

Angular separation (arcsec)

0.11300

Eq. Temperature

1,855K

(1582 °C)

Insolation (S⊕)

1,966.00

Earth = 1.00

Earth Similarity (ESI)

0.061

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

Schanche et al. 2025

Instrument

e2v CCD Camera

Publication

2025-04

Observation locale

Ground

Discovery cohort

Planets confirmed in 2025 at SuperWASP (8 shown).

WASP-154 b · Gas Giant WASP-155 b · Gas Giant WASP-116 b · Gas Giant WASP-188 b · Gas Giant WASP-197 b · Gas Giant WASP-194 b · Gas Giant WASP-195 b · Gas Giant WASP-102 b · Gas Giant

Host System: WASP-149

Spectral Class

G-type yellow (Sun-like)

Effective Temperature

5,750 K — cooler than the Sun (5,778 K)

Estimated Age

0.60 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.080 R☉

Stellar Mass

1.050 M☉

Metallicity [Fe/H]

0.00

Extended Stellar Properties

Surface gravity (log g)

4.400 dex

Stellar density

1.180 g/cm³

Metallicity ratio

[Fe/H]

Distance

211.73 parsec

Light-years 690.57 ly

V-band magnitude

11.69 mag

Voyager-speed travel 12,178,203 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

4.694 mas

Total Proper Motion

22.956 mas/yr

PM Right Ascension

-1.57 mas/yr

PM Declination

22.90 mas/yr

Galactic Cartesian (pc)

x = -0.554 · y = 0.819 · z = -0.151

Equatorial (J2000)

RA 124.07368° · Dec -8.68658°

Galactic ℓ, b

230.825° · 14.447°

Ecliptic λ, β

128.701° · -27.663°

HTM-20 index

1917132069