What it’s like to stand here
KOI-3503 c
sun
6.7× wider
sky
bright white

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

Rocky world

KOI-3503 c

KOI-3503 c is a confirmed rocky exoplanet 2,893 ly from Earth in the constellation Cygnus, discovered in 2021 by Kepler.

ESI 0.342,893 lyDiscovered in 2021 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).

KOI-3503 →
host star
1.21 R⊕
radius
10.36 M⊕
mass · measured
32 days
orbital period
413°C (775°F)
avg temp
Human scale

Its yellow-white star looks 6.7× wider than ours, bathing the surface in bright 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 32 days, and at an estimated 413°C (775°F) it is blistering.

–
your weight, not stated
EXCLUDED
32 days
one year, in Earth time
CALCULATED
6.7× wider
how big its sun looks vs ours
bright white
midday sky tint
–
jump, needs gravity
likely
likely tidally locked: probably eternal day on one side, night on the other

Catalog values (NASA Exoplanet Archive): mass 10.36 M⊕, radius 1.21 R⊕. Its catalog mass and radius imply a density of 32.2 g/cm³, denser than compressed iron, so they cannot both be right, and gravityfinder does not use KOI-3503 c in gravity rankings or weight calculations.

Earth Similarity Index0.34CALCULATED#1,905 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 413°C (775°F), sound would travel roughly 54% 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 ≈ 525 m/s · 1.54× 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
★★☆☆☆
Reconsider travel
  • !Blistering at about 413°C (775°F), far too hot for liquid water on the surface.
  • !Its star delivers about 53 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 KOI-3503 c’s measured and computed values, not a real advisory.

How long to get there · 2,893 ly awayCALCULATED
Jet airliner
3.5 billion years
dies en route1000-yr cryo: fails
Parker Solar Probethe fastest craft ever built
4.5 million years
dies en route1000-yr cryo: fails
Light speed
2,893 years
dies en route1000-yr cryo: fails
Warp 10
3 years
arrives, just older
Folding spacetimeinstant, plus 1 hr of paperwork
1 hour
arrives thriving
Size vs Earth
EarthKOI-3503 c is 1.2× 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
LARGE TELESCOPE NEEDED
Host-star brightnessmag 13.8
ConstellationCygnus →
To see the host star10"+ (250 mm) telescope, dark sky
Gear bridge

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

Common questions

How far is KOI-3503 c from Earth?

KOI-3503 c lies about 2,893 light-years from Earth.

How long would it take to get to KOI-3503 c?

At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 4.5 million years.

How hot is KOI-3503 c?

KOI-3503 c's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 413°C (775°F).

How long is a year on KOI-3503 c?

KOI-3503 c completes one orbit of its star in 32 days.

Illustration generated from KOI-3503 c's confirmed parameters, not a photograph.