What it’s like to stand here
Kepler-126 d
sun
3.0× wider
sky
bright white

Illustration computed from this world’s measured and derived values, not a photograph.

Kepler-126 d

Kepler-126 d is a confirmed sub-Neptune exoplanet 774 ly from Earth in the constellation Cygnus, discovered in 2014 by Kepler.

ESI 0.38774 lyDiscovered in 2014 by Kepler

Transit: spotted by the tiny, repeating dip in its star’s light each time the planet crosses in front of it (what that means).

Kepler-126 →
host star
2.50 R⊕
radius
54.59 M⊕
mass · minimum (m·sin i)
100 days
orbital period
202°C (395°F)
avg temp
Human scale

Its yellow-white star looks 3.0× wider than ours, bathing the surface in bright white light. A year passes in just 100 days, and at an estimated 202°C (395°F) it is blistering.

–
your weight, not stated
EXCLUDED
100 days
one year, in Earth time
CALCULATED
3.0× wider
how big its sun looks vs ours
bright white
midday sky tint
–
jump, needs gravity
normal
day/night cycle (not tidally locked)

Catalog values (NASA Exoplanet Archive): mass 54.59 M⊕, radius 2.50 R⊕. Its catalog mass and radius imply a density of 19.3 g/cm³, denser than compressed iron, so they cannot both be right, and gravityfinder does not use Kepler-126 d in gravity rankings or weight calculations.

Earth Similarity Index0.38CALCULATED#1,460 of 5,873 ranked worlds

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 202°C (395°F), sound would travel roughly 28% 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.

sound speed ≈ 437 m/s · 1.28× Earth · assumes Earth-like air

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.

The journey
Cosmic travel advisory
★★★☆☆
For seasoned travelers
  • !Blistering at about 202°C (395°F), far too hot for liquid water on the surface.

A playful read of Kepler-126 d’s measured and computed values, not a real advisory.

How long to get there · 774 ly awayCALCULATED
Jet airliner
929 million years
dies en route1000-yr cryo: fails
Parker Solar Probethe fastest craft ever built
1.2 million years
dies en route1000-yr cryo: fails
Light speed
774 years
dies en route1000-yr cryo: survives
Warp 10
283 days
arrives thriving
Folding spacetimeinstant, plus 1 hr of paperwork
1 hour
arrives thriving
Size vs Earth
EarthKepler-126 d is 2.5× the width of Earth
Explore from here · roam the neighborhood

Zoom out: star → system → (soon) galaxy arm, host black hole, and a real image of the host galaxy.

Can you see it tonight? · observe
SMALL TELESCOPE NEEDED
Host-star brightnessmag 10.5
ConstellationCygnus →
To see the host star4-6" (100-150 mm) telescope
Gear bridge

Matched telescope & eyepiece recommendations are coming. Any product links will carry a clear affiliate disclosure.

Common questions

How far is Kepler-126 d from Earth?

Kepler-126 d lies about 774 light-years from Earth.

How long would it take to get to Kepler-126 d?

At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 1.2 million years.

How hot is Kepler-126 d?

Kepler-126 d's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 202°C (395°F).

How long is a year on Kepler-126 d?

Kepler-126 d completes one orbit of its star in 100 days.

Illustration generated from Kepler-126 d's confirmed parameters, not a photograph.