A group of astronomers has recently made a most surprising discovery: three planets of the same system orbit perpendicularly around the same star. Two of them do so on the poles of the celestial body, while the third runs along the line of its equator., as reported The New York Times. It is the first time that a phenomenon of these characteristics has been observed in the History of Astronomy.
The responsible of the study explain that this star system, discovered in 2016 and located 150 light years from ours, already attracted the attention of scientists five years ago, when they observed the rotation of the two aforementioned planets on the poles, something unusual if we compare it with the Solar System, where all the planets orbit on the line of the equator of the Sun. Now it has been revealed that it is even more peculiar than they already thought.
The two planets that orbit the poles of the star, called HD3167, are farthest from it, while the one that rotates on the equator of the celestial body is the closest. These circumstances invite astronomers to think that the different trajectories may be due to the fact that the outermost ones are subjected to the force of an “invisible object” not discovered yet.
In fact, a study from the University of Exeter, in England, points out that there are many signs of the existence of a fourth Jupiter-sized planet very close to the outer two, whose gravitational effect could have changed their orbits and would explain this phenomenon, while the one closest to the star, far from its reach, would maintain its translation on the axis of the equator of HD3167.
The influence of this fourth planet on the two exteriors already discovered is explained by its proximity. The two outer bodies complete their orbit around the star HD3167 every 30 days, the inner one every 8 days and the fourth, still undiscovered, would do so every 80 days or so. In our Solar System, although there are also planets of colossal dimensions, the distance is much greater, so its gravitational effect on the rest is not strong enough to radically change their orbits.
Star systems with planets orbiting the star poles are rare, but not unheard of. Astronomers had already documented this fact before. Nevertheless, they had never before observed that the planets of the same system had perpendicular orbits.