A massive failed star is orbiting a sun-like star on a wild, eight-year loop that perfectly aligns with two small inner planets.
April 29, 2026
Original Paper
A very eccentric brown dwarf coplanar to a warm Jupiter and a hot super Earth
arXiv · 2604.23926
The Takeaway
The TOI-201 system contains a giant brown dwarf and two planets that all sit on the exact same flat plane. This is the first time such a massive object has been found in a coplanar arrangement with smaller planets on such a long orbit. Usually, large objects like brown dwarfs kick smaller planets out of their neat orbits, making the system a chaotic mess. This discovery provides a rare laboratory to study how small worlds can survive and thrive even when a giant neighbor is present. It challenges the idea that massive companions always destroy the stability of a planetary system.
From the abstract
In transiting planetary systems, where planetary sizes are accurately determined from transit observations, the presence of transit timing variations (TTVs), especially when combined with radial velocity (RV) data, provides powerful constraints on masses and orbital eccentricities. Together, these measurements offer crucial insights into system architecture, formation mechanisms, and dynamical evolution. We present long-term RV and transit/TTV monitoring of the active and young star (age $\sim$1