Bars Across Time: Tracing Galactic Structures Over 12 Billion Years

Using JWST data, Zoe Le Conte and collaborators traced how stellar bars in disc galaxies evolved over 12 billion years. They found the bar fraction declines from 16% at z ≈ 1–2 to 7% at z ≈ 4, showing that stable discs already existed early in cosmic history. Bar lengths stayed roughly constant, indicating that bars and galaxy discs have grown together over time.