When Stars Collide: Evidence for a Stellar Flyby in the Solar System’s Past
Susanne Pfalzner and colleagues propose that a close stellar flyby early in the Solar System’s history explains both the orbits and colors of trans-Neptunian objects. Their simulations show that such a flyby naturally produces the observed patterns, with red TNOs remaining in low-inclination orbits and grey ones populating higher inclinations and eccentricities. Upcoming observations could test these predictions.
A Deep Dive into the Solar System’s Outer Frontier: Pan-STARRS Hunts for Distant Worlds
Holman et al. used Pan-STARRS1 data to search for distant solar system objects, identifying 692 candidates, including 109 new ones. They developed a novel detection method using synthetic populations and machine learning. Although Planet Nine was not found, the study narrowed its possible location to the galactic plane and demonstrated a powerful framework for future surveys.
A Binary Within a Binary: Unraveling the Secrets of the Logos-Zoe System in the Outer Solar System
The Logos-Zoe system, a binary in the Kuiper Belt, is likely a rare triple system with Logos itself being a contact binary. Observations and modeling reveal a 17.43-hour rotation period for Logos and hint at a slow-rotating or complex-shaped Zoe. An upcoming mutual event season from 2026–2029 offers a unique chance to study their physical properties and system dynamics.
Unlocking the Solar System’s Secrets: The Journey of Giant Planets and Distant Trans-Neptunian Objects
V. V. Emel’yanenko’s study of the Nice model shows how migrating giant planets scattered planetesimals, forming distant trans-Neptunian objects (TNOs) like Sedna. Simulations over 4 billion years reveal that specific planetary resonances and disk conditions can reproduce the Solar System’s structure and explain TNOs.
Understanding the Colors and Movements of Trans-Neptunian Objects: A Dive into Their Origins and Dynamics
The study analyzes 696 trans-Neptunian objects (TNOs) to explore their sizes, colors, and shapes, linking them to their formation regions and migration. Two main color groups, NIRF and NIRB, reveal distinct origins, with Cold Classicals being mostly NIRF and dynamically excited classes showing mixed populations. The findings support models of Solar System evolution and provide insights into planetesimal formation and Neptune's migration.
Investigating the Orbit of a Potential 'Planet X' in the Outer Solar System
Siraj and colleagues explore the possibility of a hidden "Planet X" in the outer Solar System by analyzing clustering patterns in the orbits of distant trans-Neptunian objects (TNOs). They find statistically significant clustering that may indicate the gravitational influence of an unseen planet with around 4.4 Earth masses, located approximately 290 AU from the Sun. Their simulations suggest that this hypothetical planet could be detected by future surveys, especially the upcoming Vera C. Rubin Observatory, which could confirm the existence of Planet X.