Key parameters at a glance
- A radius of 20.96 Earth radii
- A mass of 2,154.89 Earth masses
- Surface gravity around 4.90 g
- An orbital period of 2.744 days
- Semi-major axis 0.0474 AU
- Equilibrium temperature 2,562 K (2289 °C)
- Distance from Earth 1,078.73 light-years
- Earth Similarity Index 0.045
- Travel time at Voyager 1 speed 19,023,316 years
HAT-P-70 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#23of 1771
top 1.2%
This planet
20.96R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | HAT-P-70 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 20.96 | 11.21 |
| Mass (M⊕) | 1.00 | 2,154.89 | 317.83 |
| Density (g/cm³) | 5.51 | 1.54 | 1.33 |
| Surface Gravity (g) | 1.00 | 4.90 | 2.53 |
| Insolation (S⊕) | 1.00 | 5,405.60 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 2,154.887 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
HD
HD 287325
TIC
TIC 399870368
Gaia DR2
Gaia DR2 3291455819447952768
Gaia DR3
Gaia DR3 3291455819447952768
System
HAT-P-70
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 2.74 Earth days (0.8% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0474 AU.
Transit Fingerprint
Depth
0.844 %
Duration
3.480 h
Impact parameter b
-0.629
Rp / R★
0.098870
Transit midpoint (BJD)
2,458,439.5752
Photometric dip
Transit produces a flux drop of 8,443 ppm lasting ≈ 3.48 h.
Extended Orbital Architecture
Planet / star radius ratio
0.098870
Semi-major axis / stellar radius
5.450
Impact parameter (b)
-0.629
RV semi-amplitude (K)
649.000 m/s
Transit mid-time (BJD)
2,458,439.5752
Sky-projected obliquity (λ)
113.10°
Angular separation (arcsec)
0.14300
Eq. Temperature
2,562K
(2289 °C)
Insolation (S⊕)
5,405.60
Earth = 1.00
Earth Similarity (ESI)
0.045
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched.
Discovery Paper
Primary reference
Zhou et al. 2019Instrument
2K CCD Sensor
Publication
2019-10
Observation locale
Ground
Host System: HAT-P-70
Spectral Class
A-type white
Effective Temperature
8,450 K — hotter than the Sun (5,778 K)
Estimated Age
0.60 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.858 R☉
Stellar Mass
1.890 M☉
Metallicity [Fe/H]
-0.06
Extended Stellar Properties
Surface gravity (log g)
4.181 dex
Stellar density
0.404 g/cm³
Systemic radial velocity
25.26 km/s
Rotational v·sin i
99.85 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 14 bands
Astrometric Data
Parallax
2.996 mas
Total Proper Motion
5.659 mas/yr
PM Right Ascension
-2.66 mas/yr
PM Declination
-5.00 mas/yr
Galactic Cartesian (pc)
x = 0.262 · y = 0.949 · z = 0.174
Equatorial (J2000)
RA 74.55233° · Dec 9.99798°
Galactic ℓ, b
189.965° · -19.661°
Ecliptic λ, β
74.404° · -12.609°
HTM-20 index
-19893053
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