- sun
- 28.2× wider
- sky
- dim red
Illustration computed from this world’s measured and derived values, not a photograph.
Kepler-42 c
Kepler-42 c is a confirmed rocky exoplanet 131 ly from Earth in the constellation Cygnus, discovered in 2011 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).
Its red dwarf looks 28.2× wider than ours, bathing the surface in dim red 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 10.9 hours, and at an estimated 447°C (836°F) it is furnace-hot.
Catalog values (NASA Exoplanet Archive): mass 60.34 M⊕, radius 0.73 R⊕. Its catalog mass and radius imply a density of 854.6 g/cm³, denser than compressed iron, so they cannot both be right, and gravityfinder does not use Kepler-42 c 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 447°C (836°F), sound would travel roughly 58% 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 447°C (836°F), with no liquid water and no shade anywhere.
- !Its star delivers about 82 times the sunlight Earth gets, a blinding, sterilizing glare.
- !Earth-similarity index 0.16: 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 Kepler-42 c’s measured and computed values, not a real advisory.
How long to get there · 131 ly awayCALCULATED
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 Kepler-42 c from Earth?
Kepler-42 c lies about 131 light-years from Earth.
How long would it take to get to Kepler-42 c?
At the speed of NASA's Parker Solar Probe, the fastest craft ever built, the journey would take about 203,773 years.
How hot is Kepler-42 c?
Kepler-42 c's equilibrium temperature, the balance it reaches from its star's light alone before any greenhouse warming, is about 447°C (836°F).
How long is a year on Kepler-42 c?
Kepler-42 c completes one orbit of its star in 10.9 hours.
Illustration generated from Kepler-42 c's confirmed parameters, not a photograph.