Key parameters at a glance
- A radius of 17.93 Earth radii
- A mass of 441.78 Earth masses
- Surface gravity around 1.37 g
- An orbital period of 2.735 days
- Semi-major axis 0.0442 AU
- Equilibrium temperature 2,048 K (1775 °C)
- Distance from Earth 445.79 light-years
- Earth Similarity Index 0.051
- Travel time at Voyager 1 speed 7,861,564 years
KELT-7 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#75of 1771
top 4.2%
This planet
17.93R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | KELT-7 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 17.93 | 11.21 |
| Mass (M⊕) | 1.00 | 441.78 | 317.83 |
| Density (g/cm³) | 5.51 | 0.44 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.37 | 2.53 |
| Insolation (S⊕) | 1.00 | 1,775.39 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 441.784 M⊕ | Direct mass measurement (not derived). |
| Minimum mass (M sin i) | 406.822 M⊕ | Lower bound from radial-velocity fitting. |
| Computed mass | 409.000 M⊕ | Model-computed mass (e.g. from mass-radius relation). |
Star Catalogue Identifiers
HD
HD 33643
HIP
HIP 24323
TIC
TIC 367366318
Gaia DR2
Gaia DR2 181908842994567936
Gaia DR3
Gaia DR3 181908842994567936
System
KELT-7
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 2.73 Earth days (0.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0442 AU.
Transit Fingerprint
Depth
0.830 %
Duration
3.511 h
Impact parameter b
0.593
Rp / R★
0.092200
Transit midpoint (BJD)
2,459,109.1384
Photometric dip
Transit produces a flux drop of 8,300 ppm lasting ≈ 3.51 h.
Extended Orbital Architecture
Planet / star radius ratio
0.092200
Semi-major axis / stellar radius
5.500
Impact parameter (b)
0.593
RV semi-amplitude (K)
138.000 m/s
Transit mid-time (BJD)
2,459,109.1384
Sky-projected obliquity (λ)
2.70°
Angular separation (arcsec)
0.32300
Eq. Temperature
2,048K
(1775 °C)
Insolation (S⊕)
1,775.39
Earth = 1.00
Earth Similarity (ESI)
0.051
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
Bieryla et al. 2015Instrument
Apogee 4K CCD Sensor
Publication
2015-07
Observation locale
Ground
Host System: KELT-7
Spectral Class
F-type yellow-white
Effective Temperature
6,768 K — hotter than the Sun (5,778 K)
Estimated Age
1.30 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.810 R☉
Stellar Mass
1.760 M☉
Metallicity [Fe/H]
0.00
Extended Stellar Properties
Surface gravity (log g)
4.500 dex
Stellar density
0.420 g/cm³
Systemic radial velocity
40.75 km/s
Rotational v·sin i
69.30 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 12 bands
Astrometric Data
Parallax
7.288 mas
Total Proper Motion
50.900 mas/yr
PM Right Ascension
10.62 mas/yr
PM Declination
-49.78 mas/yr
Galactic Cartesian (pc)
x = 0.170 · y = 0.818 · z = 0.549
Equatorial (J2000)
RA 78.29559° · Dec 33.31795°
Galactic ℓ, b
172.513° · -3.365°
Ecliptic λ, β
80.075° · 10.281°
HTM-20 index
-90062852
Observation Record
Photometric series
1
Transmission spectra
9
Emission spectra
9
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