Researchers unveil unusual orbital behavior in exoplanet TOI-1408c

Researchers unveil unusual orbital behavior in exoplanet TOI-1408c
by Robert Schreiber
Berlin, Germany (SPX) Sep 06, 2024

A research team led by Lund University in Sweden has identified an exoplanet exhibiting peculiar orbital movement, challenging current understandings of planetary system dynamics. This newly discovered planet, TOI-1408c, located 455 light-years away, appears to be involved in complex interactions with its larger neighbor, TOI-1408b, a hot gas giant.

TOI-1408c, with a mass approximately eight times that of Earth, orbits close to TOI-1408b. Upon further examination of the star TOI-1408 and its planets, researchers noted an unexpected orbital motion for the smaller planet. This intriguing behavior has led them to compare the planetary interactions to a "rhythmic dance" between the planets and their star.

"The small planet exhibits very unusual orbital behaviour and shows considerable variations regarding the time when it passes in front of its star, which is something that we don't see as a rule. The small planet's existence challenges existing theories on the formation and stability of planetary systems," explained Judith Korth, an astrophysicist at Lund University and leader of the study.

This study, published in 'The Astrophysical Journal Letters', highlights the complexity of planetary systems, presenting TOI-1408c as a unique case study. The planet's interaction with its neighboring gas giant may provide insights into how planets in other systems develop and evolve.

"Our results will help researchers to learn more about how planets are formed and how they behave when they are very close to each other, particularly in systems with giant planets," Korth added.

Exoplanets are worlds beyond our solar system, with over 5,700 confirmed discoveries since 1995. The detection of TOI-1408c was made possible through NASA's Transiting Exoplanet Survey Satellite (TESS), which has identified over 7,000 potential exoplanets since its launch in 2018.

"I hope that our results can be used in future studies to discover even more planets in other systems, but also to better understand the large range of planetary systems that exist in our galaxy," Korth concluded.

Research Report:TOI-1408: Discovery and Photodynamical Modeling of a Small Inner Companion to a Hot Jupiter Revealed by Transit Timing Variations