Solar System Migration Points to a Renewed Concept: Galactic Habitable Orbits

Abstract

Astrophysical evidence suggests that the Sun was born near 5 kpc from the Galactic center, within the corotation radius of the Galactic bar, around 6-7 kpc. This presents challenges for outward migration due to the Jacobi energy constraint, preventing stars from easily overcoming the corotation barrier. In this study, we use test particle simulations to explore two possible migration pathways for the Sun: a "trapped" scenario, where the Sun's orbit was influenced by a slowing Galactic bar, and an "untrapped" scenario driven by dynamic spiral arms. Our results demonstrate that both mechanisms can explain how the Sun migrated from its birth radius (approximately 5 kpc) to its current orbital radius around 8.5-9 kpc. Furthermore, we investigate the environmental changes experienced by the Sun along these migration pathways, focusing on variations in radiation hazards and comet fluxes, which may have impacted planetary habitability. These findings highlight the dynamic nature of galactic habitability, emphasizing that the path a star takes within the Milky Way can significantly affect its surrounding environment and the potential for life. We propose a new concept of "Galactic habitable orbits," which accounts for evolving galactic structures and their effects on stellar and planetary systems. This work contributes to a deeper understanding of the solar system's migration and its implications for habitability within the Milky Way.

accepted for publication in ApJ Letters

References in corpus (16)

• The Supernova -- Gamma-Ray Burst Connection
• Present-day cosmic abundances. A comprehensive study of nearby early B-type stars and implications for stellar and Galactic evolution and interstellar dust models
• Sedna and the Oort Cloud Around a Migrating Sun
• Injection of Oort Cloud Comets: The Fundamental Role of Stellar Perturbations
• Quantifying stellar radial migration in an N-body simulation: blurring, churning, and the outer regions of galaxy discs
• Chemical evolution library for galaxy formation simulation
• Revisiting long-standing puzzles of the Milky Way: the Sun and its vicinity as typical outer disk chemical evolution
• Unveiling the time evolution of chemical abundances across the Milky Way disk with APOGEE
• Orbital tori for non-axisymmetric galaxies
• Eventful Evolution of Giant Molecular Clouds in Dynamically Evolving Spiral Arms
• The completeness-corrected rate of stellar encounters with the Sun from the first Gaia data release
• The effect of the Solar motion on the flux of long-period comets
• Cosmic dust fertilization of glacial prebiotic chemistry on early Earth
• Stellar encounters with giant molecular clouds
• A comparison of the Milky Way's recent star formation revealed by dust thermal emission and high-mass stars
• Efficient radial migration by giant molecular clouds in the first several hundred Myr after the stellar birth

Cited by in corpus (4)

• Observational Constraints of Radial Migration in the Galactic Disc Driven by the Slowing Bar
• An efficient integrator for stellar dynamics in effective gravity fields based on the isochrone potential
• Rethinking Habitability using Biogenic Precursors: Formaldehyde in Millimeter Molecular Clouds of the Inner Galaxy
• Modelling the Milky Way's exoplanet population based on cosmological galaxy simulations