Key parameters at a glance
- A radius of 2.92 Earth radii
- A mass of 87.30 Earth masses
- Surface gravity around 10.24 g
- An orbital period of 17.324 days
- Semi-major axis 0.1417 AU
- Equilibrium temperature 964 K (691 °C)
- Distance from Earth 3,185.38 light-years
- Earth Similarity Index 0.232
- Travel time at Voyager 1 speed 56,174,169 years
1 sibling around Kepler-277
Kepler-277 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 |
|---|---|---|---|---|---|---|
| Kepler-277 b this | Sub-Neptune | 2.92 | 87.30 | 17.324 | 964 | 2013 |
| Kepler-277 c | Sub-Neptune | 3.36 | 64.20 | 33.006 | 778 | 2013 |
Kepler-277 b Planet Profile
Physical Specs
Classification
Planet Type
Sub-Neptune
Discovery
Size rank in cohort
Rank by radius
#600of 1978
top 30.3%
This planet
2.92R⊕
Sub-Neptune median
2.71R⊕
Nearest-size peers
| Metric | Earth | Kepler-277 b | Jupiter |
|---|---|---|---|
| Radius (R⊕) | 1.00 | 2.92 | 11.21 |
| Mass (M⊕) | 1.00 | 87.30 | 317.83 |
| Density (g/cm³) | 5.51 | 9.20 | 1.33 |
| Surface Gravity (g) | 1.00 | 10.24 | 2.53 |
| Insolation (S⊕) | 1.00 | 198.25 | 0.037 |
Alternative Mass Estimates
| Method | Value | Interpretation |
|---|---|---|
| Best measured mass | 87.300 M⊕ | Direct mass measurement (not derived). |
Star Catalogue Identifiers
TIC
TIC 120961424
Gaia DR2
Gaia DR2 2100389610777053056
Gaia DR3
Gaia DR3 2100389610777053056
System
Kepler-277
Percentile among Sub-Neptune cohort
Orbit & Habitability
Orbital Dynamics
Year Length
A year here lasts approximately 17.32 Earth days (4.7% of a terrestrial year) on a nearly circular orbit at a mean orbital distance of 0.1417 AU.
Transit Fingerprint
Depth
0.024 %
Duration
8.045 h
Impact parameter b
0.042
Rp / R★
0.014527
Transit midpoint (BJD)
2,454,975.0979
Photometric dip
Transit produces a flux drop of 241 ppm lasting ≈ 8.05 h.
Extended Orbital Architecture
Planet / star radius ratio
0.014527
Semi-major axis / stellar radius
17.020
Impact parameter (b)
0.042
Transit mid-time (BJD)
2,454,975.0979
Angular separation (arcsec)
0.14500
Eq. Temperature
964K
(691 °C)
Insolation (S⊕)
198.25
Earth = 1.00
Earth Similarity (ESI)
0.232
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.
Transit timing variations
Gravitational interactions from neighbours have been detected.
Discovery Paper
Discovery cohort
Planets confirmed in 2013 at Kepler (12 shown).
Host System: Kepler-277
Spectral Class
G-type yellow (Sun-like)
Effective Temperature
5,946 K — hotter than the Sun (5,778 K)
Estimated Age
3.89 Gyr — younger than the Sun (4.6 Gyr)
Stellar Radius
1.690 R☉
Stellar Mass
1.120 M☉
Metallicity [Fe/H]
0.09
Extended Stellar Properties
Surface gravity (log g)
4.030 dex
Stellar density
0.250 g/cm³
Metallicity ratio
[Fe/H]
Multi-band Host Photometry — 17 bands
Astrometric Data
Parallax
0.995 mas
Total Proper Motion
18.245 mas/yr
PM Right Ascension
5.82 mas/yr
PM Declination
17.29 mas/yr
Galactic Cartesian (pc)
x = 0.222 · y = -0.744 · z = 0.630
Equatorial (J2000)
RA 286.58319° · Dec 39.07726°
Galactic ℓ, b
69.944° · 14.038°
Ecliptic λ, β
297.155° · 60.962°
HTM-20 index
-779847540
Similar Worlds
Kepler-153 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.92 R⊕ · 1,498.3 ly
Kepler-1878 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.92 R⊕ · 4,873.7 ly
TOI-1203.01
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.92 R⊕ · 212.0 ly
HD 136352 c
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.92 R⊕ · 47.9 ly
HD 63935 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.92 R⊕ · 159.7 ly
Kepler-1887 b
Sub-Neptune · G-type yellow (Sun-like)
Radius 2.92 R⊕ · 4,455.9 ly