- sun
- 15.3× wider
- sky
- warm white
Illustration computed from this world’s measured and derived values, not a photograph.
TOI-251 b
TOI-251 b is a confirmed sub-Neptune exoplanet 325 ly from Earth in the constellation Sculptor, discovered in 2021 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 (what that means).
Its yellow, Sun-like star looks 15.3× wider than ours, bathing the surface in warm white 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 4.9 days, and at an estimated 768°C (1414°F) it is furnace-hot.
Catalog values (NASA Exoplanet Archive): mass 318 M⊕, radius 2.74 R⊕. Its catalog mass and radius imply a density of 85.1 g/cm³, denser than compressed iron, so they cannot both be right, and gravityfinder does not use TOI-251 b in gravity rankings or weight calculations.
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
Hear how a voice sounds herea computed acoustic demoEXPERIMENTAL · just for fun
Your voice would sound high and thin, almost cartoonish.
Assuming Earth-like air at this world's temperature of about 768°C (1414°F), sound would travel roughly 90% 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 768°C (1414°F), with no liquid water and no shade anywhere.
- !Its star delivers about 278 times the sunlight Earth gets, a blinding, sterilizing glare.
- !Earth-similarity index 0.10: this world has almost nothing in common with our own.
- !Likely tidally locked: one hemisphere in endless day, the other in permanent night.
A playful read of TOI-251 b’s measured and computed values, not a real advisory.
How long to get there · 325 ly awayCALCULATED
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.
How far is TOI-251 b from Earth?
TOI-251 b lies about 325 light-years from Earth.
How long would it take to get to TOI-251 b?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 506,249 years.
How hot is TOI-251 b?
TOI-251 b's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 768°C (1414°F).
How long is a year on TOI-251 b?
TOI-251 b completes one orbit of its star in 4.9 days.
Illustration generated from TOI-251 b's confirmed parameters, not a photograph.