Key parameters at a glance
- A radius of 2.45 Earth radii
- A mass of 6.50 Earth masses
- Surface gravity around 1.08 g
- An orbital period of 8.022 days
- Semi-major axis 0.0750 AU
- Equilibrium temperature 734 K (461 °C)
- Distance from Earth 369.15 light-years
- Earth Similarity Index 0.352
- Travel time at Voyager 1 speed 6,509,900 years
- Almost certainly tidally locked to its host star given the close orbit
1 sibling around TOI-1798
TOI-1798.01 shares its host star with 1 other confirmed planet. Side-by-side measurements below.
| Planet | Type | Radius (R⊕) | Mass (M⊕) | Period (d) | Eq. T (K) | Year |
|---|---|---|---|---|---|---|
| TOI-1798.02 | Super-Earth | 1.46 | 5.60 | 0.438 | 1,936 | 2024 |
| TOI-1798.01 this | Sub-Neptune | 2.45 | 6.50 | 8.022 | 734 | 2024 |
TOI-1798.01 Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1267of 1978
top 64.0%
This planet
2.45R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-1798.01 | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.45 | 11.21 |
| Mass (M⊕) | 1.00 | 6.50 | 317.83 |
| Density (g/cm³) | 5.51 | 2.61 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.08 | 2.53 |
| Insolation (S⊕) | 1.00 | 69.26 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 6.500 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 198153540
Gaia DR2
Gaia DR2 1505890751741673856
Gaia DR3
Gaia DR3 1505890751741673856
System
TOI-1798
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 8.02 Earth days (2.2% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0750 AU.
Transit Fingerprint
Depth
0.088 %
Duration
3.132 h
Impact parameter b
0.268
Rp / R★
0.028500
Transit midpoint (BJD)
2,459,688.1359
Photometric dip
Transit produces a flux drop of 882 ppm lasting ≈ 3.13 h.
Extended Orbital Architecture
Planet / star radius ratio
0.028500
Impact parameter (b)
0.268
RV semi-amplitude (K)
2.300 m/s
Transit mid-time (BJD)
2,459,688.1359
Long. of periastron (ω)
90.00°
Angular separation (arcsec)
0.66300
Eq. Temperature
734K
(461 °C)
Insolation (S⊕)
69.26
Earth = 1.00
Earth Similarity (ESI)
0.352
0 = alien, 1 = Earth-identical
Inside the inner HZ boundary (too hot for liquid water) — the surface is too hot to retain surface water. 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
Polanski et al. 2024Instrument
TESS CCD Array
Publication
2024-06
Observation locale
Space
Discovery cohort
Planets confirmed in 2024 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-1798
Spectral Class
K-type orange
Effective Temperature
5,165 K — cooler than the Sun (5,778 K)
Estimated Age
2.60 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
0.780 R☉
Stellar Mass
0.870 M☉
Metallicity [Fe/H]
0.07
Extended Stellar Properties
Surface gravity (log g)
4.572 dex
Stellar density
2.422 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
8.807 mas
Total Proper Motion
38.512 mas/yr
PM Right Ascension
-27.34 mas/yr
PM Declination
-27.12 mas/yr
Galactic Cartesian (pc)
x = -0.589 · y = -0.355 · z = 0.726
Equatorial (J2000)
RA 211.09394° · Dec 46.51928°
Galactic ℓ, b
91.169° · 65.856°
Ecliptic λ, β
183.629° · 53.812°
HTM-20 index
-1485569739
Similar Worlds
TOI-2345 c
Sub-Neptune · K-type orange
Radius 2.45 R⊕ · 266.3 ly
TOI-1246 c
Sub-Neptune · K-type orange
Radius 2.45 R⊕ · 552.6 ly
TOI-913 b
Sub-Neptune · K-type orange
Radius 2.45 R⊕ · 212.6 ly
Kepler-675 b
Sub-Neptune · K-type orange
Radius 2.44 R⊕ · 2,171.2 ly
Kepler-1086 b
Sub-Neptune · K-type orange
Radius 2.44 R⊕ · 1,520.2 ly
Kepler-1754 b
Sub-Neptune · K-type orange
Radius 2.44 R⊕ · 2,344.9 ly