Key parameters at a glance
- A radius of 9.40 Earth radii
- A mass of 129.00 Earth masses
- Surface gravity around 1.46 g
- An orbital period of 45.522 days
- Semi-major axis 0.2690 AU
- Equilibrium temperature 675 K (401 °C)
- Distance from Earth 259.84 light-years
- Earth Similarity Index 0.234
- Travel time at Voyager 1 speed 4,582,324 years
TOI-1898 b Planet Profile
Physical Specs
Classification
Planet Type
Neptune-like
Discovery
Size rank in cohort
Rank by radius
#51of 574
top 8.7%
This planet
9.40R⊕
Neptune-like median
6.39R⊕
Nearest-size peers
| Metric | Earth | TOI-1898 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 9.40 | 11.21 |
| Mass (M⊕) | 1.00 | 129.00 | 317.83 |
| Density (g/cm³) | 5.51 | 0.85 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.46 | 2.53 |
| Insolation (S⊕) | 1.00 | 51.01 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 129.000 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
HIP
HIP 47288
TIC
TIC 91987762
Gaia DR2
Gaia DR2 644224345413418880
Gaia DR3
Gaia DR3 644224345413418880
System
TOI-1898
Percentile among Neptune-like cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 45.52 Earth days (12.5% of a terrestrial year) on a highly eccentric trajectory at a mean orbital distance of 0.2690 AU.
Transit Fingerprint
Depth
0.303 %
Duration
4.270 h
Impact parameter b
0.700
Rp / R★
0.053399
Transit midpoint (BJD)
2,458,894.2511
Photometric dip
Transit produces a flux drop of 3,029 ppm lasting ≈ 4.27 h.
Extended Orbital Architecture
Planet / star radius ratio
0.053399
Semi-major axis / stellar radius
34.230
Impact parameter (b)
0.700
RV semi-amplitude (K)
22.900 m/s
Transit mid-time (BJD)
2,458,894.2511
Long. of periastron (ω)
70.99°
Angular separation (arcsec)
3.38000
Eq. Temperature
675K
(401 °C)
Insolation (S⊕)
51.01
Earth = 1.00
Earth Similarity (ESI)
0.234
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
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-1898
Spectral Class
F-type yellow-white
Effective Temperature
6,241 K — hotter than the Sun (5,778 K)
Estimated Age
3.10 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.613 R☉
Stellar Mass
1.248 M☉
Metallicity [Fe/H]
-0.10
Extended Stellar Properties
Surface gravity (log g)
4.116 dex
Stellar density
0.413 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
12.524 mas
Total Proper Motion
76.633 mas/yr
PM Right Ascension
-64.43 mas/yr
PM Declination
-41.49 mas/yr
Galactic Cartesian (pc)
x = -0.747 · y = 0.532 · z = 0.399
Equatorial (J2000)
RA 144.55530° · Dec 23.54675°
Galactic ℓ, b
206.473° · 46.458°
Ecliptic λ, β
139.108° · 8.920°
HTM-20 index
-1968334186
Similar Worlds
TOI-6695 b
Neptune-like · F-type yellow-white
Radius 9.53 R⊕ · 921.5 ly
Kepler-1515 b
Neptune-like · F-type yellow-white
Radius 9.55 R⊕ · 1,759.0 ly
TOI-622 b
Neptune-like · F-type yellow-white
Radius 9.24 R⊕ · 402.1 ly
HIP 41378 f
Neptune-like · F-type yellow-white
Radius 9.20 R⊕ · 346.7 ly
TOI-907.01
Neptune-like · F-type yellow-white
Radius 9.62 R⊕ · 1,019.3 ly
TOI-837 b
Neptune-like · F-type yellow-white
Radius 9.17 R⊕ · 464.7 ly