Key parameters at a glance

A radius of 19.09 Earth radii
A mass of 184.34 Earth masses
Surface gravity around 0.51 g
An orbital period of 4.007 days
Semi-major axis 0.0539 AU
Equilibrium temperature 1,766 K (1493 °C)
Distance from Earth 2,126.20 light-years
Earth Similarity Index 0.049
Travel time at Voyager 1 speed 37,495,556 years

HAT-P-64 b Planet Profile

Physical Specs

Radius

19.09 R⊕

Radius (Jupiter)

1.703 R♃

Mass

184.34 M⊕

Mass (Jupiter)

0.580 M♃

Density

0.14 g/cm³

Surface Gravity

0.51 g (Earth)

Classification

Planet Type

Gas Giant

ESI Score 0.049

HZ Position Inner

Controversial No

Discovery

Year 2021

Method Transit

Facility HATNet

Telescope Multiple Telescopes

Size rank in cohort

Rank by radius

#42of 1771

top 2.3%

This planet

19.09R⊕

Gas Giant median

13.52R⊕

Nearest-size peers

Qatar-7 b 19.06 R⊕ KELT-4 A b 19.04 R⊕ TOI-615 b 18.98 R⊕

Metric	Earth	HAT-P-64 b	Jupiter
Radius (R⊕)	1.00	19.09	11.21
Mass (M⊕)	1.00	184.34	317.83
Density (g/cm³)	5.51	0.14	1.33
Surface Gravity (g)	1.00	0.51	2.53
Insolation (S⊕)	1.00	1,611.00	0.037

Alternative Mass Estimates

Method	Value	Interpretation
Best measured mass	184.340 M⊕	Direct mass measurement (not derived).

Star Catalogue Identifiers

TIC

TIC 455036659

Gaia DR2

Gaia DR2 3279418602369232000

Gaia DR3

Gaia DR3 3279418602369232000

System

HAT-P-64

Percentile among Gas Giant cohort

Radius 19.089 R⊕ · percentile 98 / cohort 1771

Mass 184.340 M⊕ · percentile 17 / cohort 1747

Orbital period 4.01 d · percentile 29 / cohort 1533

Distance 651.90 pc · percentile 80 / cohort 1759

ESI 0.049 · percentile 4 / cohort 1771

Orbit & Habitability

Orbital Dynamics

Period

4.007 days

Semi-major axis

0.0539 AU

Eccentricity

0.101

Inclination

88.01 °

Year Length

A year here lasts approximately 4.01 Earth days (1.1% of a terrestrial year) on a mildly elliptical path at a mean orbital distance of 0.0539 AU.

Transit Fingerprint

Depth

1.036 %

Duration

4.925 h

Impact parameter b

0.232

Rp / R★

0.100700

Transit midpoint (BJD)

2,457,751.4635

Photometric dip

Transit produces a flux drop of 10,360 ppm lasting ≈ 4.93 h.

Extended Orbital Architecture

Planet / star radius ratio

0.100700

Semi-major axis / stellar radius

6.670

Impact parameter (b)

0.232

RV semi-amplitude (K)

62.000 m/s

Transit mid-time (BJD)

2,457,751.4635

Angular separation (arcsec)

0.08260

Eq. Temperature

1,766K

(1493 °C)

Insolation (S⊕)

1,611.00

Earth = 1.00

Earth Similarity (ESI)

0.049

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

Bakos et al. 2021

Instrument

Apogee 4K CCD Sensor

Publication

2021-07

Observation locale

Ground

Discovery cohort

Planets confirmed in 2021 at HATNet (6 shown).

HAT-P-59 b · Gas Giant HAT-P-61 b · Gas Giant HAT-P-63 b · Gas Giant HAT-P-62 b · Gas Giant HAT-P-58 b · Gas Giant HAT-P-60 b · Gas Giant

Host System: HAT-P-64

Spectral Class

F-type yellow-white

Effective Temperature

6,457 K — hotter than the Sun (5,778 K)

Estimated Age

2.88 Gyr — younger than the Sun (4.6 Gyr)

Stellar Radius

1.735 R☉

Stellar Mass

1.298 M☉

Metallicity [Fe/H]

-0.11

Extended Stellar Properties

Surface gravity (log g)

4.072 dex

Stellar density

0.350 g/cm³

Systemic radial velocity

25.22 km/s

Metallicity ratio

[Fe/H]

Distance

651.90 parsec

Light-years 2,126.20 ly

V-band magnitude

12.86 mag

Voyager-speed travel 37,495,556 yr

Multi-band Host Photometry — 11 bands

Astrometric Data

Parallax

1.505 mas

Total Proper Motion

8.690 mas/yr

PM Right Ascension

7.78 mas/yr

PM Declination

-3.86 mas/yr

Galactic Cartesian (pc)

x = 0.358 · y = 0.933 · z = 0.042

Equatorial (J2000)

RA 68.97440° · Dec 2.43127°

Galactic ℓ, b

193.552° · -28.451°

Ecliptic λ, β

67.661° · -19.393°

HTM-20 index

481940547