- weight
- 0.17 g
- sun
- 7.1× wider
- sky
- deep orange
Illustration computed from this world’s measured and derived values, not a photograph.
Kepler-138 b
Kepler-138 b is a confirmed rocky exoplanet 218 ly from Earth in the constellation Lyra, discovered in 2014 by Kepler.
Transit: spotted by the tiny, repeating dip in its star’s light each time the planet crosses in front of it.
Standing on Kepler-138 b, you would weigh about 83% less than you do on Earth. Its orange dwarf looks 7.1× wider than ours, bathing the surface in deep orange light. It is likely tidally locked, so that sun never moves in the sky: one hemisphere in endless day, the other in permanent night. A year passes in just 10 days, and at an estimated 179°C (354°F) it is blistering.
How closely this world matches Earth in size and warmth, from 0 to 1 (Earth = 1.0). Computed by gravityfinder. See every world ranked →
What these mean: surface gravity · tidal locking · equilibrium temperature · Earth similarity
If your children grew up herea playful thought experiment
Low gravity, 0.17 times Earth's. A child who grew up here could become strikingly tall and lightly built, about 1.4x taller than on Earth: a 5 ft 10 in adult could stand nearer 8 ft 4 in, with long limbs and slender bones.
- Bones
- Light and slender
- With little weight to carry, the growing skeleton lays down far less bone, the way astronauts' bones thin in months of low gravity.
- Heart
- Unhurried
- With less weight pulling blood down toward the feet, the heart has far less work to do.
- Movement
- Bounding and springy
- So little weight means each step would carry the body up and forward in long, floating strides.
A playful thought experiment from this world’s gravity, not a prediction about any real person. No human has ever grown up off Earth, so no one truly knows; the direction (taller in low gravity, shorter and stockier in high) follows how growing bodies respond to weight.
Hear how a voice sounds herea computed acoustic demo
Your voice would sound high and thin, almost cartoonish.
Assuming Earth-like air at this world's temperature of about 179°C (354°F), sound would travel roughly 25% faster than on Earth, so your voice would sound high and thin, almost cartoonish. The real atmosphere is unknown, so this is a best guess.
A real voice sample, pitch-shifted (tempo held constant) to suggest the acoustics: a playful approximation, not a precise simulation. Voice: Lingua Libre / Vealhurl, CC BY-SA 4.0.
- !Blistering at about 179°C (354°F), far too hot for liquid water on the surface.
- !Far too little gravity, 0.17 times Earth's, to hold a breathable atmosphere: effectively an airless vacuum.
- !Likely tidally locked: one hemisphere in endless day, the other in permanent night.
A playful read of Kepler-138 b’s measured and computed values, not a real advisory.
How long to get there · 218 ly away
Zoom out: star → system → (soon) galaxy arm, host black hole, and a real image of the host galaxy.
Matched telescope & eyepiece recommendations are coming. Any product links will carry a clear affiliate disclosure.
What is the gravity on Kepler-138 b?
Kepler-138 b's surface gravity is about 0.17 times Earth's.
How much would you weigh on Kepler-138 b?
Someone who weighs 150 pounds on Earth would weigh about 26 pounds on Kepler-138 b.
How far is Kepler-138 b from Earth?
Kepler-138 b lies about 218 light-years from Earth.
How long would it take to get to Kepler-138 b?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 340,113 years.
How hot is Kepler-138 b?
Kepler-138 b's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 179°C (354°F).
How long is a year on Kepler-138 b?
Kepler-138 b completes one orbit of its star in 10 days.
Illustration generated from Kepler-138 b's confirmed parameters, not a photograph.