Kepler Discovers an Ancient 11-Billion Year Planetary System

Kepler space telescope has made yet another significant find; A star-planet system as old as the Milky Way galaxy.

The system comprises five planets ranging in size between Mercury and Venus in orbit around the star name Kepler 444. The age of the star is estimated at 11.2 billion years. In comparison, the Sun is aged only 4.5 billion years while the universe is aged13.7 billion years, ABC News reported. The system is 117 light years away from Earth. The star however is only three-quaters the size of Sun.

"Kepler-444 formed when the universe was less than 20% of its current age and making it the oldest known system of terrestrial-size planets. 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 age of Kepler-444 not only suggests that thick-disk stars were among the hosts to the first Galactic planets, but may also help to pinpoint the beginning of the era of planet formation," researchers wrote in the Astrophysical Journal.

While the planets are proportional in size to Earth, their orbits around Kepler 444 are far smaller to that of Earth. Researchers estimated the size and diameter of the parent star while they found that the planets orbit the star in 10 days. The planets are also hotter than Mercury and inhospitable for life as we know, Xinhua reports.

However researchers are excited about the find as the system is the oldest known and can improve understanding of early planet formation processes.