Key parameters at a glance
- A radius of 2.02 Earth radii
- A mass of 2.89 Earth masses
- Surface gravity around 0.71 g
- An orbital period of 1.548 days
- Semi-major axis 0.0225 AU
- Equilibrium temperature 999 K (726 °C)
- Distance from Earth 134.10 light-years
- Earth Similarity Index 0.254
- Travel time at Voyager 1 speed 2,364,928 years
- Almost certainly tidally locked to its host star given the close orbit
1 sibling around TOI-544
TOI-544 b 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-544 b this | Sub-Neptune | 2.02 | 2.89 | 1.548 | 999 | 2022 |
| TOI-544 c | Neptune-like | 4.92 | 21.50 | 50.089 | — | 2023 |
TOI-544 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#1938of 1978
top 97.9%
This planet
2.02R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-544 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.02 | 11.21 |
| Mass (M⊕) | 1.00 | 2.89 | 317.83 |
| Density (g/cm³) | 5.51 | 1.93 | 1.33 |
| Surface Gravity (g) | 1.00 | 0.71 | 2.53 |
| Insolation (S⊕) | 1.00 | 240.20 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 2.890 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
HD
HD 290498
TIC
TIC 50618703
Gaia DR2
Gaia DR2 3220926542276901888
Gaia DR3
Gaia DR3 3220926542276901888
System
TOI-544
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 1.55 Earth days (0.4% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.0225 AU.
Transit Fingerprint
Depth
0.093 %
Duration
1.210 h
Impact parameter b
0.660
Rp / R★
0.029700
Transit midpoint (BJD)
2,459,199.0314
Photometric dip
Transit produces a flux drop of 926 ppm lasting ≈ 1.21 h.
Extended Orbital Architecture
Planet / star radius ratio
0.029700
Impact parameter (b)
0.660
RV semi-amplitude (K)
2.170 m/s
Transit mid-time (BJD)
2,459,199.0314
Long. of periastron (ω)
0.00°
Angular separation (arcsec)
0.54700
Eq. Temperature
999K
(726 °C)
Insolation (S⊕)
240.20
Earth = 1.00
Earth Similarity (ESI)
0.254
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
Giacalone et al. 2022Instrument
TESS CCD Array
Publication
2022-02
Observation locale
Space
Discovery cohort
Planets confirmed in 2022 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-544
Spectral Class
K-type orange
Effective Temperature
4,169 K — cooler than the Sun (5,778 K)
Estimated Age
9.00 Gyr — older than the Sun (4.6 Gyr)
Stellar Radius
0.623 R☉
Stellar Mass
0.631 M☉
Metallicity [Fe/H]
-0.17
Extended Stellar Properties
Surface gravity (log g)
4.680 dex
Stellar density
3.187 g/cm³
Rotation period
19.34 days
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 11 bands
Astrometric Data
Parallax
24.292 mas
Total Proper Motion
85.327 mas/yr
PM Right Ascension
34.30 mas/yr
PM Declination
-78.13 mas/yr
Galactic Cartesian (pc)
x = 0.134 · y = 0.991 · z = -0.006
Equatorial (J2000)
RA 82.29007° · Dec -0.34290°
Galactic ℓ, b
203.539° · -18.386°
Ecliptic λ, β
81.581° · -23.557°
HTM-20 index
-1656622047
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