Whatever we grow up with, we think of as normal. Our single solitary yellow star seems normal to us, with planets orbiting on the same, aligned ecliptic. But most stars aren’t alone; most are in binary relationships. And some are in triple-star systems.
And the planet-forming disks around those three-star systems can exhibit some misshapen orbits.
Two teams of astronomers using the Atacama Large Millimeter/sub-millimeter Array (ALMA) have looked into a young solar system called GW Orionis (GW Ori) that contains three stars. They’ve found that the orbits of the young, still-forming planets in this system are strange and misshapen. Their orbits are much different than the planets in our own Solar System.
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