Key parameters at a glance
- A radius of 11.99 Earth radii
- A mass of 279.69 Earth masses
- Surface gravity around 1.94 g
- An orbital period of 10.180 days
- Semi-major axis 0.0818 AU
- Equilibrium temperature 918 K (645 °C)
- Distance from Earth 498.67 light-years
- Earth Similarity Index 0.160
- Travel time at Voyager 1 speed 8,793,982 years
TOI-1478 b Planet Profile
Physical Specs
Classification
Planet Type
Gas Giant
Discovery
Size rank in cohort
Rank by radius
#1514of 1771
top 85.4%
This planet
11.99R⊕
Gas Giant median
13.52R⊕
Nearest-size peers
| Metric | Earth | TOI-1478 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 11.99 | 11.21 |
| Mass (M⊕) | 1.00 | 279.69 | 317.83 |
| Density (g/cm³) | 5.51 | 0.88 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.94 | 2.53 |
| Insolation (S⊕) | 1.00 | 261.01 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 279.689 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 409794137
Gaia DR2
Gaia DR2 5723638723350902400
Gaia DR3
Gaia DR3 5723638723350902400
System
TOI-1478
Percentile among Gas Giant cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 10.18 Earth days (2.8% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0818 AU.
Transit Fingerprint
Depth
0.109 %
Duration
4.131 h
Impact parameter b
0.636
Rp / R★
0.102000
Transit midpoint (BJD)
2,459,066.0187
Photometric dip
Transit produces a flux drop of 1,094 ppm lasting ≈ 4.13 h.
Extended Orbital Architecture
Planet / star radius ratio
0.102000
Semi-major axis / stellar radius
18.540
Impact parameter (b)
0.636
RV semi-amplitude (K)
81.500 m/s
Transit mid-time (BJD)
2,459,066.0187
Long. of periastron (ω)
94.00°
Sky-projected obliquity (λ)
6.20°
Angular separation (arcsec)
0.53500
Eq. Temperature
918K
(645 °C)
Insolation (S⊕)
261.01
Earth = 1.00
Earth Similarity (ESI)
0.160
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water.
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
Rodriguez et al. 2021Instrument
TESS CCD Array
Publication
2021-04
Observation locale
Space
Discovery cohort
Planets confirmed in 2021 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-1478
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,597 K — cooler than the Sun (5,778 K)
Estimated Age
9.10 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
1.048 R☉
Stellar Mass
0.947 M☉
Metallicity [Fe/H]
0.08
Extended Stellar Properties
Surface gravity (log g)
4.374 dex
Stellar density
1.160 g/cm³
Systemic radial velocity
21.16 km/s
Rotational v·sin i
1.24 km/s
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
6.512 mas
Total Proper Motion
68.445 mas/yr
PM Right Ascension
-8.28 mas/yr
PM Declination
67.94 mas/yr
Galactic Cartesian (pc)
x = -0.577 · y = 0.782 · z = -0.234
Equatorial (J2000)
RA 126.43374° · Dec -13.55955°
Galactic ℓ, b
236.352° · 13.834°
Ecliptic λ, β
132.757° · -31.750°
HTM-20 index
179517354
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