Key parameters at a glance
- A radius of 8.71 Earth radii
- A mass of 425.26 Earth masses
- Surface gravity around 5.61 g
- An orbital period of 16.255 days
- Semi-major axis 0.1308 AU
- Equilibrium temperature 814 K (541 °C)
- Distance from Earth 1,305.70 light-years
- Earth Similarity Index 0.237
- Travel time at Voyager 1 speed 23,026,081 years
HATS-17 b Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#104of 574
top 17.9%
This planet
8.71R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | HATS-17 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 8.71 | 11.21 |
| Mass (M⊕) | 1.00 | 425.26 | 317.83 |
| Density (g/cm³) | 5.51 | 3.50 | 1.33 |
| Surface Gravity (g) | 1.00 | 5.61 | 2.53 |
| Insolation (S⊕) | 1.00 | 72.70 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 425.257 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 73717937
Gaia DR2
Gaia DR2 6127982342061605120
Gaia DR3
Gaia DR3 6127982342061605120
System
HATS-17
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 16.25 Earth days (4.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1308 AU.
Transit Fingerprint
Depth
0.495 %
Duration
4.826 h
Impact parameter b
0.432
Rp / R★
0.072600
Transit midpoint (BJD)
2,457,139.1672
Photometric dip
Transit produces a flux drop of 4,950 ppm lasting ≈ 4.83 h.
Extended Orbital Architecture
Planet / star radius ratio
0.072600
Semi-major axis / stellar radius
25.800
Impact parameter (b)
0.432
RV semi-amplitude (K)
99.100 m/s
Transit mid-time (BJD)
2,457,139.1672
Angular separation (arcsec)
0.32700
Eq. Temperature
814K
(541 °C)
Insolation (S⊕)
72.70
Earth = 1.00
Earth Similarity (ESI)
0.237
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.
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
Brahm et al. 2016Instrument
Apogee 4K CCD Sensor
Publication
2016-04
Observation locale
Ground
Discovery cohort
Planets confirmed in 2016 at HATSouth (12 shown).
Host System: HATS-17
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,846 K — hotter than the Sun (5,778 K)
Estimated Age
2.10 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.091 R☉
Stellar Mass
1.131 M☉
Metallicity [Fe/H]
0.30
Extended Stellar Properties
Surface gravity (log g)
4.416 dex
Stellar density
1.220 g/cm³
Systemic radial velocity
22.94 km/s
Rotational v·sin i
3.73 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 14 bands
Astrometric Data
Parallax
2.471 mas
Total Proper Motion
32.183 mas/yr
PM Right Ascension
-32.06 mas/yr
PM Declination
2.83 mas/yr
Galactic Cartesian (pc)
x = -0.659 · y = -0.142 · z = -0.739
Equatorial (J2000)
RA 192.18957° · Dec -47.61368°
Galactic ℓ, b
302.464° · 15.256°
Ecliptic λ, β
212.781° · -38.393°
HTM-20 index
-1476620310
Similar Worlds
TOI-1194 b
Neptune-like · G-type yellow (Sun-like)
Radius 8.72 R⊕ · 488.1 ly
Kepler-177 c
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Kepler-108 b
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Radius 8.65 R⊕ · 1,104.8 ly
Kepler-30 d
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TOI-2364 b
Neptune-like · G-type yellow (Sun-like)
Radius 8.61 R⊕ · 716.3 ly