Worlds without end: Using archived Kepler data astronomers have identified a solar system of five Earth-sized exoplanets, orbiting a red dwarf star about 117 light years from Earth.
The paper describes Kepler-444, a star that’s 25 percent smaller than our sun and is 117 light years from Earth. The star’s five known planets have sizes that fall between Mercury and Venus. Those planets are so close to their star that they complete their orbits in fewer than 10 days. At that distance, they’re all much hotter than Mercury and aren’t habitable.
The important detail from this discovery is that the star is very ancient, more than 11 billion years old, which means these planets are that old as well. In other words, planets began forming the same time as the first stars. Which also means that there has been plenty of time in the universe for other intelligent life to form, besides our own.