LONDON: Astronomers poring over four years of data from NASA’s Kepler spacecraft have discovered a star that’s 11.2 billion years old and has at least five Earth-size planets.
“The findings 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,” said Tiago Campante, research fellow at the University of Birmingham who led the research project.
The paper describes Kepler-444, a star that is 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 are all much hotter than Mercury and are not habitable.
“Kepler-444 is very bright and can be easily seen with binoculars. This is one of the oldest systems in the galaxy,” added Steve Kawaler, an Iowa State University professor of physics and astronomy and co-author of the paper.
Kepler-444 came from the first generation of stars.”This system tells us that planets were forming around stars nearly seven billion years before our own solar system,” Kawaler noted.
Planetary systems around stars have been a common feature of our galaxy for a long, long time.That discovery is going to help astronomers learn even more about the history of the Milky Way.