- weight
- ≈ 0.39 g
- sun
- 20.3× wider
- sky
- deep orange
Illustration computed from this world’s measured and derived values, not a photograph.
GJ 238 b
GJ 238 b is a confirmed rocky exoplanet 49.6 ly from Earth in the constellation Pictor, discovered in 2024 by Transiting Exoplanet Survey Satellite (TESS).
Transit: spotted by the tiny, repeating dip in its star’s light each time the planet crosses in front of it.
Standing on GJ 238 b, you would weigh roughly about 61% less than you do on Earth. Its red dwarf looks 20.3× 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 1.7 days, and at an estimated 485°C (905°F) it is furnace-hot.
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, about 0.39 times Earth's. A child who grew up here could become strikingly tall and lightly built, about 1.2x taller than on Earth: a 5 ft 10 in adult could stand nearer 7 ft, 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 485°C (905°F), sound would travel roughly 62% 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.
- !Furnace-hot at around 485°C (905°F), with no liquid water and no shade anywhere.
- !Far too little gravity, about 0.39 times Earth's, to hold a breathable atmosphere: effectively an airless vacuum.
- !Its star delivers about 229 times the sunlight Earth gets, a blinding, sterilizing glare.
- !Likely tidally locked: one hemisphere in endless day, the other in permanent night.
A playful read of GJ 238 b’s measured and computed values, not a real advisory.
How long to get there · 49.6 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.
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What is the gravity on GJ 238 b?
GJ 238 b's surface gravity is about 0.39 times Earth's, estimated from its size.
How much would you weigh on GJ 238 b?
Someone who weighs 150 pounds on Earth would weigh about 59 pounds on GJ 238 b.
How far is GJ 238 b from Earth?
GJ 238 b lies about 49.6 light-years from Earth.
How long would it take to get to GJ 238 b?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 77,391 years.
How hot is GJ 238 b?
GJ 238 b's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 485°C (905°F).
How long is a year on GJ 238 b?
GJ 238 b completes one orbit of its star in 1.7 days.
Illustration generated from GJ 238 b's confirmed parameters, not a photograph.