Key parameters at a glance
- A radius of 2.42 Earth radii
- A mass of 6.28 Earth masses
- Surface gravity around 1.08 g
- An orbital period of 2.492 days
- Semi-major axis 0.0287 AU
- Equilibrium temperature 703 K (430 °C)
- Distance from Earth 123.57 light-years
- Earth Similarity Index 0.364
- Travel time at Voyager 1 speed 2,179,175 years
- Almost certainly tidally locked to its host star given the close orbit
TOI-1201 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1310of 1978
top 66.2%
This planet
2.42R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-1201 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.42 | 11.21 |
| Mass (M⊕) | 1.00 | 6.28 | 317.83 |
| Density (g/cm³) | 5.51 | 2.45 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.08 | 2.53 |
| Insolation (S⊕) | 1.00 | 40.60 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 6.280 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 29960110
Gaia DR2
Gaia DR2 5157183324996790272
Gaia DR3
Gaia DR3 5157183324996790272
System
TOI-1201
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 2.49 Earth days (0.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0287 AU.
Transit Fingerprint
Depth
0.209 %
Duration
1.747 h
Impact parameter b
0.404
Rp / R★
0.043830
Transit midpoint (BJD)
2,459,169.2322
Photometric dip
Transit produces a flux drop of 2,094 ppm lasting ≈ 1.75 h.
Extended Orbital Architecture
Planet / star radius ratio
0.043830
Semi-major axis / stellar radius
12.230
Impact parameter (b)
0.404
RV semi-amplitude (K)
4.650 m/s
Transit mid-time (BJD)
2,459,169.2322
Long. of periastron (ω)
90.00°
Angular separation (arcsec)
0.75800
Eq. Temperature
703K
(430 °C)
Insolation (S⊕)
40.60
Earth = 1.00
Earth Similarity (ESI)
0.364
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
Kossakowski et al. 2021Instrument
TESS CCD Array
Publication
2021-12
Observation locale
Space
Discovery cohort
Planets confirmed in 2021 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-1201
Spectral Class
M-type red dwarf
Effective Temperature
3,476 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.508 R☉
Stellar Mass
0.512 M☉
Metallicity [Fe/H]
0.05
Extended Stellar Properties
Surface gravity (log g)
4.800 dex
Stellar density
5.500 g/cm³
Rotational v·sin i
2.00 km/s
Rotation period
21.00 days
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
26.365 mas
Total Proper Motion
170.556 mas/yr
PM Right Ascension
164.06 mas/yr
PM Declination
46.63 mas/yr
Galactic Cartesian (pc)
x = 0.717 · y = 0.651 · z = -0.251
Equatorial (J2000)
RA 42.24770° · Dec -14.53728°
Galactic ℓ, b
194.188° · -59.893°
Ecliptic λ, β
34.756° · -29.286°
HTM-20 index
-1444152430
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