Particle.news
Download on the App Store
10 ARTICLES
·
yesterday

Gaia Finds Thousands of Solar Twins, Tying the Sun to a Mass Migration Across the Milky Way

The pattern points to a central bar in formation that drove outward movement of Sun-like stars, offering a constraint on when the bar emerged.

Image
The Milky Way’s central bar (yellow) is a dense region of stars that links our galaxy’s spiral arms.

Overview

  • Two companion papers in Astronomy & Astrophysics (March 12–13) present a Gaia-based catalog of 6,594 solar twins with precise ages and properties.
  • The ages show a narrow peak around 2 billion years and a broad 4–6 billion-year cohort that includes the Sun, with about 1,551 stars in this older grouping.
  • The authors propose these older stars formed nearer the galactic center and migrated roughly 10,000 light-years outward as the Milky Way’s bar was taking shape.
  • They argue the corotation barrier would have been incomplete during bar growth, enabling large-scale radial migration that helps explain the Sun’s current location.
  • Outside researchers praise the dataset but flag distance-limited sampling and orbital-bias concerns, leaving the migration interpretation plausible yet unconfirmed.