The TOI-178 System
The TOI-178 System This is an artist’s impression of the TOI-178 planetary system, which was revealed by ESA’s exoplanet watcher Cheops.The system consists of six exoplanets, five of which are locked in a rare rhythmic dance as they orbit their central star. The two inner planets have terrestrial densities (like Earth) and the outer four planets are gaseous (with densities like Neptune and Jupiter). The five outer planets follow a rhythmic dance as they move in their orbits. This phenomenon is called orbital resonance, and it means that there are patterns that repeat themselves as the planets go around the star, with some planets aligning every few orbits. ESA