The only planet that has 100% chance of life is Earth, which is the planet us humans live on.
Earth is the only celestial body and planet that is confirmed and known to host living organisms including animals and us humans.
Scientists have not yet discovered any definitive proof of any life elsewhere in the universe, although there are several exoplanets that are outside of our solar system, which are widely considered to be top candidates to host biological activity.
Earth is the only known planet with 100% chance of life, hosting millions of species including humans.
Other planets that are considered to have a 100 percent chance of life include.
Kepler-442b, which is located 1,200 light-years away, is a rocky super-Earth that receives favorable amounts of stellar radiation, giving it a notably high statistical probability of being able to harbor life.
TRAPPIST-1e, is a rocky, Earth-sized planet located 40 light-years away.
It sits squarely in its star's "Goldilocks zone," meaning surface temperatures could allow for liquid water if it has a stable atmosphere.
K2-18b, which is located roughly 120 light-years away, is a "Hycean" (water-ocean) world and is a primary candidate in the search for life.
In observations using the NASA James Webb Space Telescope, scientists detected chemical signatures in its atmosphere that are typically produced by living organisms on Earth.
Earth is the only planet known to harbor life because it uniquely combines the right chemical ingredients, a stable and continuous energy source, and a rare series of planetary defense mechanisms that allow complex organisms to thrive.
The Habitable "Goldilocks" ZoneEarth orbits at precisely the right distance from the Sun, allowing temperatures to stay within a range that keeps water in its liquid state.
Planets closer to the sun, like Venus, are too hot (evaporating any potential water), while planets farther out, like Mars, are too cold.
Crucial Planetary Conditions.
Several overlapping systems make Earth uniquely hospitable:
Protective Atmosphere: A blend of nitrogen and oxygen filters out harmful solar radiation, traps heat for a stable climate, and supplies the gases required for respiration.
Strong Magnetic Field: Earth’s large, molten core generates a magnetosphere that shields the atmosphere from devastating solar winds—a defense mechanism that Mars, for example, lost early in its history.
Active Geology: Moving tectonic plates constantly recycle carbon and other essential elements, regulating the climate over billions of years.
While Earth is the only world with confirmed life, astrobiologists suspect that simple or microscopic life could potentially exist elsewhere in our solar system (such as under the icy crusts of Jupiter's moon Europa).
Given the billions of stars and exoplanets in the universe, scientists are actively searching for other worlds with similar habitable conditions.