Kepler finds galaxy’s oldest solar system

The Kepler Space Telescope found the oldest solar system in the galaxy. While digging through backlogged data from the Kepler telescope, scientists found Kepler-444, an 11.2 billion year-old star in the Milky Way orbited by at least five Earth-sized planets.

“This is one of the oldest systems in the galaxy,” said Steve Kawaler, an astronomy professor from Iowa State University and co-author of a study of the ancient star system published this week in Astrophysical Journal. “Kepler-444 came from the first generation of stars. This system tells us that planets were forming around stars nearly 7 billion years before our own solar system.”

By comparison, our sun is much younger — 4.5 billion years old.

The star is 117 light years from Earth and about a quarter the size of the Sun. It is so bright it can easily be seen with binoculars, Kawaler said.

Kepler-444’s planets range from the size of Mercury to the size of Earth. At their current orbit, they couldn’t support life. On the surface, they are hotter than Mercury and finish an orbit every 10 days.

This finding tells scientists about the history of our Milky Way Galaxy, but it also means that there could have been other planets like Earth in the ancient universe, the study’s authors said.

“We thus show that Earth-size planets have formed throughout most of the Universe’s 13.8-billion-year history, leaving open the possibility for the existence of ancient life in the Galaxy,” the paper stated.