Astronomers have used an array of telescopes, including the Very Large Telescope ESO, to observe a system of six exoplanets. The interesting thing about this system is that five of the exoplanets are locked in a rare rhythm around the central star. Astronomers believe the system could provide important clues about how planets formed and evolved, including those in our solar system.
The star At the center is called TOI-178 and is about 200 light-years away in the constellation of the Sculptor. Scientists originally thought they had discovered a pair of exoplanets orbiting the star in the same orbit. Moreover, the examination revealed that there were no planets orbiting a star at roughly the same distance but multiple planets in a special configuration.
Research has confirmed that the system includes six exoplanets and that all but the closest outer planets are trapped in a rhythmic dance as they rotate. Planets have an echo, which means there are patterns that repeat themselves as planets rotate around the stars. Some planets line up in every few orbits.
In our solar system, a similar echo is observed in the orbits of three of Jupiter’s moons, Io, Europa, and Ganymede. TOI-178’s five exoplanets follow a more complex series of resonances, the longest ever discovered in the planetary system to date. Jupiter’s three moons echo 4: 2: 1, while the five outer planets of TOI-178 follow an 18: 9: 6: 4: 3 series.
The second planet of the star completes 18 revolutions, the third one completes nine orbits, and so on. Initially, only five planets were discovered in the system. After the resonance, researchers can calculate the whereabouts of an additional planet when they have the next opportunity to observe it. Researchers say the resonance shows that the system is well-organized and has developed gently from birth.