Kepler-442b might sustain life better than Earth, but step onto its surface and your body would immediately weigh 30 percent more.
Discovered in 2015 by NASA's Kepler mission, this rocky super-Earth orbits inside the habitable zone of an orange dwarf star about 1,194 light-years away, earning an Earth Similarity Index score of 0.84. Planetary scientists frequently cite it as a prime candidate for a superhabitable world—a planet whose baseline conditions could theoretically prove even more welcoming to biology than Earth.
Much of that appeal comes down to its parent star. Unlike volatile red dwarfs, which regularly batter nearby worlds with sterilizing radiation flares, Kepler-442 is a calm K-type dwarf. These stars burn steadily for tens of billions of years, far outlasting the Sun. Orbiting at roughly 0.41 astronomical units with a 112-day year, Kepler-442b sits far enough out that it may have avoided tidal locking. Rather than having one scorched hemisphere facing perpetual noon while the other freezes in eternal dark, it could maintain a rotating day-and-night cycle.
That extra weight stems from the planet's dimensions. Kepler-442b has a radius about 1.34 times that of Earth and an estimated mass 2.36 times greater, creating that 1.3g surface gravity. A person weighing 160 pounds on Earth would carry nearly 210 pounds there. The human skeleton and cardiovascular system could physically endure the load, but ordinary movement would demand constant exertion, and prolonged strain on blood circulation would pose gradual health risks.
The decisive obstacle is that astronomers have no data on the planet's actual atmosphere. At a distance of nearly 1,200 light-years, existing instruments cannot detect whether Kepler-442b possesses surface water, a protective magnetic field, breathable gases, or a crushing runaway greenhouse shroud. Even if the environment proved hospitable, getting there is an impossible hurdle: traveling that distance at the speed of the Voyager 1 probe would take roughly 21 million years.