Orbital Resonance
Scientists have discovered that the planets surrounding the HD 158259 star are in an almost perfect orbital harmony.
About the Stellar System
The stellar system of HD 158259 is composed of 6 planets. One of them is a super-earth and the other 5 are mini-neptunes. This planet system is 88 light years away from our solar system. It was studied using the TESS exoplanet hunting space telescope.
Meaning of Orbital Resonance
The term orbital resonance means that the orbits of 2 bodies around their host star are closely linked together. This is because of the gravitational force exerted by the bodies on each other. In our solar system, the phenomenon is very rare. Pluto and Neptune show resonance in the ratio of 2:3- meaning for every 2 laps completed by Pluto, Neptune completes 3.
Orbital Resonance in HD 158259 System
The 6 planet system shows almost perfect orbital resonance. These planets have a period ratio of 1.5. Each planet is in a 3:2 resonance with the next planet out from the star-i.e. for every 3 orbits completed by a planet, the next planet from the star completes 2. Scientists have recorded such systems with orbital resonance in the past also. Eg: TRAPPIST-1 and Kepler-80.