University of Birmingham

Discovered by the University of Birmingham-led team in 2015, the Kepler-444 system is a celestial marvel, holding the title of the oldest known system with Earth-sized planets. Situated in the constellation of Lyra, approximately 119 light-years from Earth, this system intrigues astronomers with its unique structure — a primary star orbited closely by five planets smaller than Venus, and a companion star in a highly eccentric orbit. The Kepler mission’s transit method data has been pivotal in studying this system’s unusual planetary dynamics, which challenge preconceived notions of planetary motion. Researchers employ the Numerical Analysis of Fundamental Frequencies (NAFF) to decipher the complex orbital dance of these planets. With the addition of high-precision data from instruments like HIRES and Gaia, and observations hinting at a possible sixth planet, Kepler-444 continues to redefine our understanding of planet formation and evolution in multi-star systems.