Newly discovered 6 planets

Astronomers have discovered a strange star system called TOI-178 with six planets and the outer five orbit in perfect harmony, a phenomenon known as resonance. Other planetary systems have been seen to be in resonance but this is the first time that the planets involved are so wildly different from one another. In a few already known systems with such a harmony, the density of planets steadily decreases as we move away from the star. But in the case of TOI-178 system, a dense, terrestrial planet like Earth appears to be right next to a very fluffy planet with half the density of Neptune followed by one very similar to Neptune. The system, therefore, challenges our understanding of the formation and evolution of planetary systems.