Key parameters at a glance
- A radius of 21.41 Earth radii
- A mass of 1,293.57 Earth masses
- Surface gravity around 2.82 g
- An orbital period of 4.612 days
- Semi-major axis 0.0637 AU
- Equilibrium temperature 1,935 K (1662 °C)
- Distance from Earth 979.37 light-years
- Earth Similarity Index 0.057
- Travel time at Voyager 1 speed 17,271,157 years
KELT-19 A b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#20of 1771
top 1.1%
This planet
21.41R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | KELT-19 A b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 21.41 | 11.21 |
| Mass (M⊕) | 1.00 | 1,293.57 | 317.83 |
| Density (g/cm³) | 5.51 | 0.74 | 1.33 |
| Surface Gravity (g) | 1.00 | 2.82 | 2.53 |
| Insolation (S⊕) | 1.00 | 2,340.00 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 1,293.568 M⊕ | Direct mass measurement (not derived). |
| Minimum mass (M sin i) | 1,287.212 M⊕ | Lower bound from radial-velocity fitting. |
Star Catalogue Identifiers
TIC
TIC 425206121
Gaia DR2
Gaia DR2 3142847477107193344
Gaia DR3
Gaia DR3 3142847477107193344
System
KELT-19
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 4.61 Earth days (1.3% of a terrestrial year) at a mean orbital distance of 0.0637 AU.
Transit Fingerprint
Depth
1.148 %
Duration
4.394 h
Impact parameter b
0.601
Rp / R★
0.107130
Transit midpoint (BJD)
2,457,281.2495
Photometric dip
Transit produces a flux drop of 11,480 ppm lasting ≈ 4.39 h.
Extended Orbital Architecture
Planet / star radius ratio
0.107130
Semi-major axis / stellar radius
7.500
Impact parameter (b)
0.601
RV semi-amplitude (K)
352.000 m/s
Transit mid-time (BJD)
2,457,281.2495
Sky-projected obliquity (λ)
-179.70°
Angular separation (arcsec)
0.21200
Eq. Temperature
1,935K
(1662 °C)
Insolation (S⊕)
2,340.00
Earth = 1.00
Earth Similarity (ESI)
0.057
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.
Transit timing variations
Gravitational interactions from neighbours have been detected.
Discovery Paper
Primary reference
Siverd et al. 2018Instrument
Multiple Instruments
Publication
2018-01
Observation locale
Ground
Host System: KELT-19 A
Spectral Class
A-type white
Effective Temperature
7,500 K — hotter than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
1.830 R☉
Stellar Mass
1.620 M☉
Metallicity [Fe/H]
-0.12
Extended Stellar Properties
Surface gravity (log g)
4.127 dex
Stellar density
0.376 g/cm³
Systemic radial velocity
-8.50 km/s
Rotational v·sin i
84.80 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 14 bands
Astrometric Data
Parallax
3.302 mas
Total Proper Motion
3.163 mas/yr
PM Right Ascension
-2.85 mas/yr
PM Declination
-1.37 mas/yr
Galactic Cartesian (pc)
x = -0.363 · y = 0.922 · z = 0.133
Equatorial (J2000)
RA 111.50953° · Dec 7.61578°
Galactic ℓ, b
210.012° · 11.134°
Ecliptic λ, β
112.012° · -14.195°
HTM-20 index
-1697865925
Similar Worlds
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WASP-178 b
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bet Pic b
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