Key parameters at a glance
- A radius of 17.60 Earth radii
- A mass of 149.38 Earth masses
- Surface gravity around 0.48 g
- An orbital period of 5.477 days
- Semi-major axis 0.0694 AU
- Equilibrium temperature 1,740 K (1467 °C)
- Distance from Earth 1,755.08 light-years
- Earth Similarity Index 0.052
- Travel time at Voyager 1 speed 30,950,800 years
WASP-172 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#91of 1771
top 5.1%
This planet
17.60R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | WASP-172 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 17.60 | 11.21 |
| Mass (M⊕) | 1.00 | 149.38 | 317.83 |
| Density (g/cm³) | 5.51 | 0.16 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.48 | 2.53 |
| Insolation (S⊕) | 1.00 | 1,506.50 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 149.380 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 453789494
Gaia DR2
Gaia DR2 6086712585429729536
Gaia DR3
Gaia DR3 6086712585429729536
System
WASP-172
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 5.48 Earth days (1.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0694 AU.
Transit Fingerprint
Depth
0.720 %
Duration
5.294 h
Impact parameter b
0.450
Rp / R★
0.084900
Transit midpoint (BJD)
2,457,032.2617
Photometric dip
Transit produces a flux drop of 7,200 ppm lasting ≈ 5.29 h.
Extended Orbital Architecture
Planet / star radius ratio
0.084900
Semi-major axis / stellar radius
8.000
Impact parameter (b)
0.450
RV semi-amplitude (K)
42.000 m/s
Transit mid-time (BJD)
2,457,032.2617
Sky-projected obliquity (λ)
115.00°
True obliquity (ψ)
112.00°
Angular separation (arcsec)
0.12900
Eq. Temperature
1,740K
(1467 °C)
Insolation (S⊕)
1,506.50
Earth = 1.00
Earth Similarity (ESI)
0.052
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
Hellier et al. 2019Instrument
iKon-L CCD Camera
Publication
2019-01
Observation locale
Ground
Discovery cohort
Planets confirmed in 2018 at SuperWASP-South (12 shown).
Host System: WASP-172
Spectral Class
F-type yellow-white
Effective Temperature
6,900 K — hotter than the Sun (5,778 K)
Estimated Age
1.79 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.910 R☉
Stellar Mass
1.490 M☉
Metallicity [Fe/H]
-0.10
Extended Stellar Properties
Surface gravity (log g)
4.050 dex
Stellar density
0.300 g/cm³
Systemic radial velocity
-20.28 km/s
Rotational v·sin i
13.70 km/s
Rotation period
7.00 days
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
1.831 mas
Total Proper Motion
15.984 mas/yr
PM Right Ascension
-15.98 mas/yr
PM Declination
0.51 mas/yr
Galactic Cartesian (pc)
x = -0.640 · y = -0.226 · z = -0.734
Equatorial (J2000)
RA 199.43374° · Dec -47.23757°
Galactic ℓ, b
307.557° · 15.398°
Ecliptic λ, β
217.944° · -35.714°
HTM-20 index
-1861643636
Similar Worlds
HATS-39 b
Gas Giant · F-type yellow-white
Radius 17.60 R⊕ · 2,865.3 ly
KELT-18 b
Gas Giant · F-type yellow-white
Radius 17.60 R⊕ · 1,048.2 ly
HAT-P-39 b
Gas Giant · F-type yellow-white
Radius 17.61 R⊕ · 2,273.3 ly
KELT-3 b
Gas Giant · F-type yellow-white
Radius 17.49 R⊕ · 685.7 ly
WASP-167 b
Gas Giant · F-type yellow-white
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HATS-40 b
Gas Giant · F-type yellow-white
Radius 17.71 R⊕ · 4,378.0 ly