Key parameters at a glance
- A radius of 12.72 Earth radii
- A mass of 1,938.76 Earth masses
- Surface gravity around 11.98 g
- An orbital period of 1.805 days
- Semi-major axis 0.0280 AU
- Equilibrium temperature 1,385 K (1112 °C)
- Distance from Earth 1,073.17 light-years
- Earth Similarity Index 0.122
- Travel time at Voyager 1 speed 18,925,363 years
- Almost certainly tidally locked to its host star given the close orbit
Qatar-4 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#1127of 1771
top 63.6%
This planet
12.72R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | Qatar-4 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 12.72 | 11.21 |
| Mass (M⊕) | 1.00 | 1,938.76 | 317.83 |
| Density (g/cm³) | 5.51 | 5.10 | 1.33 |
| Surface Gravity (g) | 1.00 | 11.98 | 2.53 |
| Insolation (S⊕) | 1.00 | 614.00 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 1,938.763 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 440113053
Gaia DR2
Gaia DR2 385697172809355392
Gaia DR3
Gaia DR3 385697172809355392
System
Qatar-4
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 1.81 Earth days (0.5% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0280 AU.
Transit Fingerprint
Depth
1.902 %
Duration
2.138 h
Impact parameter b
0.310
Rp / R★
0.137900
Transit midpoint (BJD)
2,457,637.7736
Photometric dip
Transit produces a flux drop of 19,020 ppm lasting ≈ 2.14 h.
Extended Orbital Architecture
Planet / star radius ratio
0.137900
Semi-major axis / stellar radius
7.110
Impact parameter (b)
0.310
RV semi-amplitude (K)
1,087.000 m/s
Transit mid-time (BJD)
2,457,637.7736
Angular separation (arcsec)
0.08520
Eq. Temperature
1,385K
(1112 °C)
Insolation (S⊕)
614.00
Earth = 1.00
Earth Similarity (ESI)
0.122
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the dayside is scorched. Close-orbiting tidally-locked around a cool host.
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
Alsubai et al. 2017Instrument
FLI ProLine 4K CCD Sensor
Publication
2017-04
Observation locale
Ground
Discovery cohort
Planets confirmed in 2017 at Qatar (3 shown).
Host System: Qatar-4
Spectral Class
K-type orange
Effective Temperature
5,215 K — cooler than the Sun (5,778 K)
Estimated Age
0.17 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.849 R☉
Stellar Mass
0.896 M☉
Metallicity [Fe/H]
0.10
Extended Stellar Properties
Surface gravity (log g)
4.533 dex
Stellar density
2.070 g/cm³
Systemic radial velocity
-28.76 km/s
Rotational v·sin i
7.10 km/s
Rotation period
6.05 days
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
3.011 mas
Total Proper Motion
8.921 mas/yr
PM Right Ascension
0.99 mas/yr
PM Declination
-8.87 mas/yr
Galactic Cartesian (pc)
x = 0.716 · y = 0.061 · z = 0.695
Equatorial (J2000)
RA 4.85928° · Dec 44.02760°
Galactic ℓ, b
116.876° · -18.468°
Ecliptic λ, β
24.882° · 37.838°
HTM-20 index
-275933713
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