- weight
- ≈ 1.12 g
- sun
- 3.4× wider
- sky
- deep orange
Illustration computed from this world’s measured and derived values, not a photograph.
K2-9 b
K2-9 b is a confirmed sub-Neptune exoplanet 271 ly from Earth in the constellation Virgo, 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 K2-9 b, you would weigh roughly about 12% more than you do on Earth. Its red dwarf looks 3.4× 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 18 days, and at an estimated 41°C (106°F) it is warm.
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
Gravity close to Earth's, at about 1.1 times. A child would grow up much as they would back home.
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 41°C (106°F), sound would travel roughly 4% faster than on Earth, so your voice would sound much as it does on Earth. 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.
- Surface temperatures near 41°C (106°F) fall in the range where liquid water is at least possible.
- Surface gravity is close to Earth's, about 1.12 times, so you would move much as you do here.
- !Likely tidally locked: one hemisphere in endless day, the other in permanent night.
A playful read of K2-9 b’s measured and computed values, not a real advisory.
How long to get there · 271 ly away
No other confirmed planets here yet. New ones auto-appear as telescopes report.
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 K2-9 b?
K2-9 b's surface gravity is about 1.1 times Earth's, estimated from its size.
How much would you weigh on K2-9 b?
Someone who weighs 150 pounds on Earth would weigh about 169 pounds on K2-9 b.
How far is K2-9 b from Earth?
K2-9 b lies about 271 light-years from Earth.
How long would it take to get to K2-9 b?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 422,013 years.
How hot is K2-9 b?
K2-9 b's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 41°C (106°F).
Is K2-9 b habitable?
K2-9 b orbits near its star's habitable zone, the range of distances where liquid water could be stable, and its Earth-similarity index is 0.69. 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 K2-9 b?
K2-9 b completes one orbit of its star in 18 days.
Illustration generated from K2-9 b's confirmed parameters, not a photograph.