Astronomers have discovered six planets that Orbital resonance revolve around a bright star. The perfect harmony between the orbits of these planets has been maintained since 4 billion years ago. Researchers have recently published a paper in Nature magazine described
The discovery of this system could give astronomers a unique opportunity to trace the evolution of its universes back to when they first formed, and potentially gain valuable knowledge about how the Solar System got to its current state. Raphael Luke, an astronomer at the University of Chicago and lead author of the study told the New York Times“It’s like looking at a fossil. “Today’s orbit of the planets is the same as it was a billion years ago.”
Researchers think that when planets first form, their orbits are aligned around the star. In other words, the time it takes for one planet to orbit the parent star may be exactly two or three times the second planet orbits the star.
Systems whose planets align in this way experience a phenomenon known as orbital resonance. However, resonance is extremely rare in the Milky Way, and only one percent of planetary systems still retain this resonance.
Most of the time, the orbits of the planets lose their alignment due to an event that upsets the gravitational balance of the system. This event can be a close collision with another star, the formation of a massive planet like Jupiter, or a destructive collision of one of the planets with another mass and the formation of a ripple effect on other orbits. According to Dr. Luke, when such an event occurs, the orbit of the planets becomes so irregular that it is impossible to describe them mathematically and to understand the history of the evolution of the planets.
Finding even a pair of exoplanets in a state of resonance is a great stroke of luck for astronomers; But in the newly discovered star system, there are surprisingly five pairs; Because all six planets have orbits that are in harmony with each other. Dr. Luke describes such a discovery as “one percent of one percent.”
The researchers used data from 12 telescopes, including NASA’s Transiting Extrasolar Mapping Satellite (TESS), to describe the system. For the first time in 2020, this satellite observed planets passing in front of their parent star. Subsequent observations by the European Exoplanet Surveyor Satellite (CHEOPS) helped the researchers understand the relationship between the orbits.
The innermost planet completes its orbit every 9.1 days. This planet completes its orbit three times in the same time that the second planet orbits the star exactly twice (27.2 days). The same ratio exists between the orbital periods of the second and third planets as well as the third and fourth planets. The last pair are also rotating in a different ratio to each other: four rotations of the fifth planet equal three rotations of the sixth planet.
Although orbital resonance is a rare finding, the planets themselves are all larger than Earth and smaller than Neptune, or in other words, some of the most common types of worlds in the galaxy. Because the parent star is bright enough to be seen by ground-based telescopes, continuous monitoring of the system will be possible in the future.
With more data, astronomers can better determine the masses and sizes of planets and even learn about their internal compositions and atmospheres. Such knowledge could expand our imagination about the conditions of planets that could potentially harbor life. This knowledge could also reveal the secrets of the structure of our own solar system and help scientists to discover the chaos that causes the loss of harmony between the planets.