- weight
- 1.14 g
- sun
- 0.03× as wide
- sky
- warm white
Illustration computed from this world’s measured and derived values, not a photograph.
Neptune
Neptune is a Neptune-like world in our own solar system.
Neptune is a giant ball of gas with no solid surface to stand on; you would simply sink into ever-thicker cloud. From here the Sun looks 0.03× as wide as it does from Earth, bathing the cloud tops in warm white light. A year here lasts 165 Earth years, and at an estimated -201°C (-330°F) it is colder than almost anywhere in the solar system.
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
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 1.1 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 604 metres per second, 1.8 times its Earth speed, flipping a voice into a thin, cartoon-helium squeak.
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.
- !No surface to stand on, only crushing cloud above a slushy interior.
- !The fastest winds in the solar system, around 2,000 km/h.
- !This far out, the Sun is barely a thousandth as bright as it is on Earth.
A playful read of Neptune’s measured and computed values, not a real advisory.
Neptune is in our own solar system. It orbits about 30.07 AU from the Sun, so sunlight reaches it in roughly 250 minutes. From Earth it is about 29.07 AU away at closest, and a spacecraft is far slower:
How long to get there with today’s craft
At the speed of the Parker Solar Probe, the fastest craft ever built, the trip to Neptune would take about 262 days; a real mission took Voyager 2 about 12 years.
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 Neptune?
Neptune is a gas giant with no solid surface to stand on. At its cloud tops, gravity pulls about 1.1 times as hard as Earth's.
How hot is Neptune?
Neptune's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about -201°C (-330°F).
How long is a year on Neptune?
Neptune completes one orbit of the Sun in 165 years.
The portrait of Neptune is a real photograph (NASA / JPL, Public domain). The "stand here" scene and the size comparison are computed illustrations, not photographs.