Relative sizes of the newly discovered habitable-zone planets and Earth. Left to right: Kepler-69c, Kepler-62e, Kepler-62f and Earth (except for Earth, these are artists' renditions). Image credit: ...

— -- Astronomers on Monday reported the discovery of an Earth-like planet outside the solar system whose size and distance from its own star put it in the "habitable" zone and make for a surface ...

635 light-years from where you are sitting, way out in outer space, lies a planet. The first planet to be discovered inside ...

If our Moon suddenly vanished, Earth would already face dramatic consequences. But replacing it with entire alien worlds ...

We’ve learned that Earth-sized planets aren’t alone out there. Thanks to missions like NASA’s Kepler and TESS telescopes, we’ve spotted dozens of rocky worlds ...

Computer simulations suggest NASA’s Habitable Worlds Observatory could detect Earth-like exomoons around gas giant exoplanets through reflected starlight and lunar eclipses.

The planets have been nicknamed Earth's seven sisters. — -- An international team of astronomers has discovered seven potentially habitable exoplanets — or planets outside our solar system — that ...

Our solar system may be the odd one out. Across the Milky Way, astronomers keep finding super-Earths, planets larger than our ...

One group of experts now say that looking for life on water and oxygen-rich planets could be a waste of time.