- weight
- ≥ 4.01 g
- sun
- 1.2× wider
- sky
- warm white
Illustration computed from this world’s measured and derived values, not a photograph.
HD 4203 b
HD 4203 b is a confirmed gas-giant exoplanet 265 ly from Earth in the constellation Pisces, discovered in 2001 by W. M. Keck Observatory.
Radial Velocity: spotted by the gravitational wobble the planet tugs in its star.
HD 4203 b is a giant ball of gas with no solid surface to stand on; you would simply sink into ever-thicker cloud. Its yellow, Sun-like star looks 1.2× wider than ours, bathing the cloud tops in warm white light. A year here lasts 432 days, and at an estimated 24°C (75°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
There is no ground here to grow up on, only bottomless sky. A child could never stand, walk, or even fall to a surface, because there isn't one. Under about 4.0 times Earth's gravity and pressure that only climbs the deeper you go, anything built for this world would not look human at all: picture something closer to a deep-sea creature than a person, broad and buoyant, drifting through the cloud decks with no need for legs and no floor to land on.
- Body plan
- Floating, not upright
- With no surface and no fixed up or down, a skeleton built for standing would be useless; a drifting, gas-filled body would not.
- Build
- Broad and pressure-hardened
- Pressure rises without limit toward the interior, so anything alive would have to be built like a deep-sea animal, not a land one.
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 a thin, helium-fast squeak.
There is no surface to stand on; this is the sound at the cloud tops, where the air is mostly hydrogen and helium, the lightest gases there are. Sound races through them at about 1,227 metres per second, 3.6 times its Earth speed, flipping a voice into a thin, cartoon-helium squeak. The temperature behind that number is this world's computed equilibrium temperature; its real atmosphere is unknown. The demo plays the shift capped at 1.8x; the real effect would be even stronger.
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 24°C (75°F) fall in the range where liquid water is at least possible.
- !There is nowhere to land: no ground, no deck, only cloud that thickens into crushing pressure.
A playful read of HD 4203 b’s measured and computed values, not a real advisory.
How long to get there · 265 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 HD 4203 b?
HD 4203 b is a gas giant with no solid surface to stand on. At its cloud tops, gravity pulls at least 4.0 times as hard as Earth's.
How far is HD 4203 b from Earth?
HD 4203 b lies about 265 light-years from Earth.
How long would it take to get to HD 4203 b?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 413,958 years.
How hot is HD 4203 b?
HD 4203 b's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 24°C (75°F).
Is HD 4203 b habitable?
HD 4203 b orbits near its star's habitable zone, the range of distances where liquid water could be stable, and its Earth-similarity index is 0.43. 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 HD 4203 b?
HD 4203 b completes one orbit of its star in 432 days.
Illustration generated from HD 4203 b's confirmed parameters, not a photograph.