Key parameters at a glance
- A radius of 2.65 Earth radii
- A mass of 7.51 Earth masses
- Surface gravity around 1.07 g
- An orbital period of 3.994 days
- Semi-major axis 0.0269 AU
- Equilibrium temperature 588 K (315 °C)
- Distance from Earth 210.92 light-years
- Earth Similarity Index 0.419
- Travel time at Voyager 1 speed 3,719,618 years
- Almost certainly tidally locked to its host star given the close orbit
TOI-277 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#946of 1978
top 47.8%
This planet
2.65R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | TOI-277 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.65 | 11.21 |
| Mass (M⊕) | 1.00 | 7.51 | 317.83 |
| Density (g/cm³) | 5.51 | 2.22 | 1.33 |
| Surface Gravity (g) | 1.00 | 1.07 | 2.53 |
| Insolation (S⊕) | 1.00 | 28.24 | 0.037 |
Star Catalogue Identifiers
TIC
TIC 439456714
Gaia DR2
Gaia DR2 2353440974955205632
Gaia DR3
Gaia DR3 2353440974955205632
System
TOI-277
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 3.99 Earth days (1.1% of a terrestrial year) at a mean orbital distance of 0.0269 AU.
Transit Fingerprint
Depth
0.580 %
Duration
1.969 h
Impact parameter b
0.360
Transit midpoint (BJD)
2,459,119.8264
Photometric dip
Transit produces a flux drop of 5,802 ppm lasting ≈ 1.97 h.
Eq. Temperature
588K
(315 °C)
Insolation (S⊕)
28.24
Earth = 1.00
Earth Similarity (ESI)
0.419
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.
Discovery Paper
Primary reference
Magliano et al. 2022Instrument
TESS CCD Array
Publication
2022-11
Observation locale
Space
Discovery cohort
Planets confirmed in 2022 at Transiting Exoplanet Survey Satellite (TESS) (12 shown).
Host System: TOI-277
Spectral Class
K-type orange
Effective Temperature
4,031 K — cooler than the Sun (5,778 K)
Estimated Age
—
Stellar Radius
0.362 R☉
Stellar Mass
0.160 M☉
Metallicity [Fe/H]
-0.01
Extended Stellar Properties
Surface gravity (log g)
4.580 dex
Stellar density
4.754 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 7 bands
Astrometric Data
Parallax
15.435 mas
Total Proper Motion
274.616 mas/yr
PM Right Ascension
-115.43 mas/yr
PM Declination
-249.18 mas/yr
Galactic Cartesian (pc)
x = 0.883 · y = 0.305 · z = -0.358
Equatorial (J2000)
RA 19.07670° · Dec -20.95328°
Galactic ℓ, b
166.842° · -81.615°
Ecliptic λ, β
8.869° · -26.712°
HTM-20 index
-1551907263
Similar Worlds
HD 39194 c
Sub-Neptune · K-type orange
Radius 2.65 R⊕ · 86.1 ly
K2-212 b
Sub-Neptune · K-type orange
Radius 2.65 R⊕ · 356.2 ly
TOI-1064 c
Sub-Neptune · K-type orange
Radius 2.65 R⊕ · 222.0 ly
K2-165 d
Sub-Neptune · K-type orange
Radius 2.65 R⊕ · 439.0 ly
Kepler-1822 b
Sub-Neptune · K-type orange
Radius 2.65 R⊕ · 2,927.6 ly
Kepler-1110 b
Sub-Neptune · K-type orange
Radius 2.66 R⊕ · 2,370.6 ly