Host star — Kepler-61
- Spectral type
- K7 V
- Temperature
- 4,017 K
- Radius
- 0.62 R☉
- Mass
- 0.64 M☉
- Luminosity
- 0.107 L☉
- Distance
- 335.1 pc (1,093 ly)
Orange dwarf, cooler and longer-lived than the Sun.
Cooler than the Sun. Orange or red dwarf.
Kepler-61 b
Orbits Kepler-61 · 1,093 light-years from Earth
Super-EarthTransit2013ESI 80 · Very Earth-like
Radius
2.15×
Earth
Mass
5.3×
Earth
Year
60d
Temp
273 K
0°C
Gravity
1.1×
Earth
Distance
1,093
ly
Could life exist here?
AI analysisKepler-61 b orbits a cool K-type star about 1,090 light-years away, and its equilibrium temperature sits at a temperate 273 Kelvin—right at Earth's freezing point. The planet itself is a super-Earth with 2.15 times our planet's radius and 5.27 Earth masses, giving it a density of 2.91 g/cm³ that suggests a rocky composition with a modest atmosphere. Its 59.9-day orbit places it within the habitable zone, though the moderate eccentricity of 0.25 means temperature swings across its year. The major caveat is distance: at over a thousand light-years away, we cannot directly observe its atmosphere or surface conditions, leaving open critical questions about whether any water persists as liquid, whether toxic volcanic outgassing dominates, or whether the atmosphere has escaped entirely. The habitability score of 80 reflects these tantalizing indicators, but ground truth requires future atmospheric spectroscopy that remains decades away. Kepler-61 b's discovery via the transit method in 2013 makes it an enduring benchmark for how temperate super-Earths challenge our definitions of habitability.
What it would be like
Kepler-61 b is a super-Earth — larger than our planet but likely still rocky or ice-rich. Whether it has a thin atmosphere like Mars or a crushing one like Venus remains unknown.
Surface gravity is about 1.1g — noticeably heavier what you're used to on Earth.
With an equilibrium temperature around 0°C, this planet sits in the temperature range where liquid water could potentially exist on the surface — a key ingredient for life as we know it.
An orbital period of 60 days makes the year 6.1× shorter than Earth's. You'd celebrate your birthday more often here.
Earth comparison
Logarithmic bars so Jupiter-class planets fit the same scale as Earth-size worlds.
Radius2.15R⊕
1/25×Earth = 125×
Mass5.27M⊕
1/10000×Earth = 110000×
Surface gravity1.14g
1/100×Earth = 1100×
Equilibrium temp273 K(0°C)
0 KEarth 255 K2500 K
Side-by-side with Earth
Temperature in context
Liquid N₂Mars avgEarth eq.Earth sfc.Boiling H₂OVenus
Discovery & orbit
- Method
- Transit
- Year
- 2013
- Facility
- Kepler
- Semi-major axis
- 0.2486 AU
- Period
- 59.88 days
- Eccentricity
- 0.2500
- Density
- 2.91 g/cm³
Detected by measuring the tiny dip in starlight as the planet crosses in front of its star.
Noticeably elliptical. Seasons (if any) would vary in intensity.
Low density — probably icy or gas-rich.
Discovered via · Transit
Tiny dip in starlight as the planet crosses in front of its star
A transit photometer watches a star nonstop and measures its brightness to ~0.01%. When a planet passes between us and the star, the star dims briefly — the deeper the dip, the bigger the planet. This is how Kepler and TESS found most known exoplanets.
- Overall share
- ~75% of all confirmed worlds
- Best for
- Earth-to-Neptune-sized planets on short orbits
Orbital Animation
Kepler-61Kepler-61 bOrbitHabitable zone
Drag to rotate · scroll to zoomSemi-major axis: 0.249 AUEccentricity: 0.2500Period: 59.9 days
Hertzsprung–Russell Diagram
Where this host star sits among … exoplanet host stars. The main sequence band runs diagonally — giants and supergiants sit above, white dwarfs below.
OBAFGKMCurrent star
How far is 1,093 light-years?
- A light beam leaving Earth right now would arrive in 1,093 years.
- At Voyager 1's speed (17 km/s), the trip would take approximately 19.3 million years.
- A radio signal sent today would arrive in 1092.9 years — and the reply wouldn't come back for twice that.
Earth Similarity Index
80/1000 — Nothing like Earth100 — Identical to Earth
ESI combines radius similarity and equilibrium temperature similarity. Earth = 100. Mars ≈ 73. Venus ≈ 44. This score reflects two physical parameters only — not atmosphere, water, or magnetic field.