A planetary system baffles scientists: "Its behavior is strange and has never been recorded before."

 

Earth

A planetary system baffles scientists: "Its behavior is strange and has never been recorded before."

The discovery of a rare and unusual planetary system has baffled astronomers, after it was observed using NASA's TESS spacecraft and the ASTEP project in the frozen plateau of Antarctica.

The exoplanets orbiting the star TOI-201 have orbits that change remarkably rapidly, to the point that scientists have been able to observe these changes in real time, a behavior never before recorded in any other planetary system, according to the space science website Space.com.
This system is located approximately 370 light-years from Earth. The star TOI-201 is slightly larger than our Sun, with a mass and diameter about 1.3 times that of the Sun.

3 extremely contrasting planets

The system includes three very different planets: a super-Earth rocky planet with a mass six times that of Earth and a year of only 5.8 days, a gas giant known as TOI-201b with a mass half that of Jupiter and a year of 53 days, and a massive gas giant with a mass 16 times that of Jupiter and a year that extends to 7.9 Earth years (2,883 days).

One of the team members from the University of Birmingham explained that most planetary systems tend to be similar and orbitally close, adding: "But this is not the case with the TOI-201 system, where the three planets are clearly different and interact gravitationally with each other."

Although changes in planetary orbits are a known phenomenon, they usually occur over millions or billions of years, what distinguishes the TOI-201 system is that these changes occur in much shorter time periods.

Each planet behaves differently

This is attributed to the highly elongated and inclined orbit of the giant outer gas planet, which exerts a gravitational influence on the inner planets, altering the direction of their orbits and the timing of their transits in front of the star. Scientists indicate that, if this interaction continues, these planets may not align in front of their star for approximately 200 years.

Tristan Guillou of the Côte d'Azur Observatory said: "In our solar system, the planets orbit in nearly identical planes, but here each planet behaves differently, indicating active orbital reorganization within the system."

As team leader Ismail Meireles added, "Our goal wasn't just to find out what the system contains, but to understand how its planets dynamically interact." The TESS mission detected a rare transit of the exoplanet, while ground-based telescopes captured its gravitational influence on the star.

Scientists also recorded unusual delays in the transit of planet TOI-201b, with one researcher noting that the planet began its transit about half an hour later than expected, which was considered an important indicator of gravitational interactions within the system.

The researchers emphasize that this discovery would not have been possible without the telescopes located in Antarctica, which provide unique observational conditions, opening new horizons for understanding the evolution of planetary systems similar to our solar system.