Key parameters at a glance
- A radius of 3.46 Earth radii
- A mass of 73.20 Earth masses
- Surface gravity around 6.11 g
- An orbital period of 1.244 days
- Semi-major axis 0.0213 AU
- Equilibrium temperature 1,479 K (1206 °C)
- Distance from Earth 538.50 light-years
- Earth Similarity Index 0.143
- Travel time at Voyager 1 speed 9,496,445 years
- Almost certainly tidally locked to its host star given the close orbit
TOI-1853 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#193of 1978
top 9.7%
This planet
3.46R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-1853 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 3.46 | 11.21 |
| Mass (M⊕) | 1.00 | 73.20 | 317.83 |
| Density (g/cm³) | 5.51 | 9.74 | 1.33 |
| Surface Gravity (g) | 1.00 | 6.11 | 2.53 |
| Insolation (S⊕) | 1.00 | 435.33 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 73.200 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 73540072
Gaia DR2
Gaia DR2 1233227944114002688
Gaia DR3
Gaia DR3 1233227944114002688
System
TOI-1853
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 1.24 Earth days (0.3% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0213 AU.
Transit Fingerprint
Depth
0.179 %
Duration
1.190 h
Impact parameter b
0.520
Transit midpoint (BJD)
2,459,690.7420
Photometric dip
Transit produces a flux drop of 1,790 ppm lasting ≈ 1.19 h.
Extended Orbital Architecture
Impact parameter (b)
0.520
RV semi-amplitude (K)
48.800 m/s
Transit mid-time (BJD)
2,459,690.7420
Angular separation (arcsec)
0.12900
Eq. Temperature
1,479K
(1206 °C)
Insolation (S⊕)
435.33
Earth = 1.00
Earth Similarity (ESI)
0.143
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
Naponiello et al. 2023Instrument
TESS CCD Array
Publication
2023-09
Observation locale
Space
Discovery cohort
Planets confirmed in 2023 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-1853
Spectral Class
K-type orange
Effective Temperature
4,985 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.808 R☉
Stellar Mass
0.837 M☉
Metallicity [Fe/H]
0.11
Extended Stellar Properties
Surface gravity (log g)
4.490 dex
Stellar density
1.953 g/cm³
Rotational v·sin i
1.30 km/s
Activity index (log R'HK)
-4.730
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 16 bands
Astrometric Data
Parallax
6.028 mas
Total Proper Motion
47.258 mas/yr
PM Right Ascension
-45.63 mas/yr
PM Declination
-12.31 mas/yr
Galactic Cartesian (pc)
x = -0.816 · y = -0.499 · z = 0.292
Equatorial (J2000)
RA 211.45935° · Dec 16.99237°
Galactic ℓ, b
6.263° · 70.041°
Ecliptic λ, β
202.722° · 27.818°
HTM-20 index
1198737197
Similar Worlds
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TOI-1246 d
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TOI-5076 b
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Kepler-357 d
Sub-Neptune · K-type orange
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TOI-5789 e
Sub-Neptune · K-type orange
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Kepler-712 b
Sub-Neptune · K-type orange
Radius 3.41 R⊕ · 2,845.7 ly