An international team of scientists has uncovered three Earth-sized exoplanets within the TOI-2267 binary star system, situated approximately 190 light-years from Earth. This significant discovery, detailed in a recent publication in Astronomy & Astrophysics, challenges existing theories regarding the processes of planet formation and stability in binary star systems.
According to Sebastian Zuniga-Fernandez from the University of Liege (ULiege), the TOI-2267 system is noteworthy as it represents the first known binary star system where transiting planets orbit both stars. TOI-2267 itself is characterized as a compact binary system, where two stars closely orbit each other, creating a potentially unstable environment for the formation of planets.
Despite these challenges, the research team successfully identified three Earth-sized planets with short orbital periods around these stars. Francisco J. Pozuelos from the Instituto de Astrofisica de Andalucia (IAA-CSIC) noted that this finding establishes TOI-2267 as the most compact and coldest pair of stars known to host planets.
The initial detection of the two planets was accomplished by astronomers at ULiege and IAA-CSIC using their proprietary detection software named SHERLOCK. This early identification initiated a series of follow-up observations conducted from ground-based facilities. The confirmation of the planetary signals necessitated extensive collaborative efforts involving multiple observatories, including the SPECULOOS and TRAPPIST telescopes operated by ULiege. These robotic telescopes are specifically designed to investigate small exoplanets that orbit faint stars, playing a crucial role in verifying the planets” existence.
Zuniga-Fernandez expressed that the discovery of three Earth-sized planets within a compact binary system provides a rare opportunity to explore the limits of current planet formation models in such complex environments. Pozuelos further emphasized the importance of this system, describing it as a natural laboratory for comprehending how rocky planets can form and persist under extreme dynamic conditions.
This groundbreaking discovery raises significant questions about the mechanisms of planet formation in binary systems and paves the way for future investigations utilizing advanced telescopes, including the James Webb Space Telescope (JWST).
