- weight
- 1.59 g
- sun
- 2.9× wider
- sky
- deep orange
Illustration computed from this world’s measured and derived values, not a photograph.
K2-18 b
K2-18 b is a confirmed sub-Neptune exoplanet 124 ly from Earth in the constellation Leo, discovered in 2015 by K2.
Transit: spotted by the tiny, repeating dip in its star’s light each time the planet crosses in front of it.
Standing on K2-18 b, you would weigh about 59% more than you do on Earth. Its red dwarf looks 2.9× 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 33 days, and at an estimated 11°C (52°F) it is cold.
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 · habitable zone
If your children grew up herea playful thought experiment
A little heavier than home, at 1.6 times Earth's gravity. A child raised here would likely grow a little shorter and sturdier than their Earth-raised parents, about 0.91x as tall as on Earth: a 5 ft 10 in adult could stand nearer 5 ft 4 in, with denser bones.
- Bones
- Thick and dense
- More weight to bear forces the skeleton to grow denser and stronger all through childhood.
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 much as it does on Earth.
Assuming Earth-like air at this world's temperature of about 11°C (52°F), sound would travel close to its Earth speed, so your voice would sound much as it does on Earth. The real atmosphere is unknown.
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.
- Surface temperatures near 11°C (52°F) fall in the range where liquid water is at least possible.
- !Noticeably heavy, 1.6 times Earth's gravity.
- !Likely tidally locked: one hemisphere in endless day, the other in permanent night.
A playful read of K2-18 b’s measured and computed values, not a real advisory.
How long to get there · 124 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 K2-18 b?
K2-18 b's surface gravity is about 1.6 times Earth's.
How much would you weigh on K2-18 b?
Someone who weighs 150 pounds on Earth would weigh about 238 pounds on K2-18 b.
How far is K2-18 b from Earth?
K2-18 b lies about 124 light-years from Earth.
How long would it take to get to K2-18 b?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 193,432 years.
How hot is K2-18 b?
K2-18 b's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 11°C (52°F).
Is K2-18 b habitable?
K2-18 b orbits near its star's habitable zone, the range of distances where liquid water could be stable, and its Earth-similarity index is 0.77. That makes it worth studying, but it is not evidence of life: we have no measurement of its atmosphere, water, or surface.
How long is a year on K2-18 b?
K2-18 b completes one orbit of its star in 33 days.
Illustration generated from K2-18 b's confirmed parameters, not a photograph.