Astronomers Discover Ancient System with Five Small Planets

Source: NASA

The tightly packed system, named Kepler-444, is home to five planets that range in size, the smallest comparable to the size of Mercury and the largest to Venus. All five planets orbit their sun-like star in less than ten days, which makes their orbits much closer than Mercury’s sweltering 88-day orbit around the sun.

“While this star formed a long time ago, in fact before most of the stars in the Milky Way, we have no indication that any of these planets have now or ever had life on them,” said Steve Howell, Kepler/K2 project scientist at NASA’s Ames Research Center in Moffett Field, California. “At their current orbital distances, life as we know it could not exist on these ancient worlds.”

Kepler-444 formed 11.2 billion years ago, when the universe was less than 20 percent its current age. This makes Kepler-444 the oldest known system of terrestrial-size planets, two and a half times older than the Earth.

The Kepler-444 system is approximately 117 light-years away toward the constellation Lyra.