space Paradigm Challenge

The universe’s first galaxies grew up and got organized way faster than anyone thought possible—it’s like they skipped their awkward teenage years.

April 13, 2026

Original Paper

The Hubble sequence in JWST CEERS from unbiased galaxy morphologies

Elizaveta Sazonova, Cameron R. Morgan, Michael Balogh

arXiv · 2604.08682

The Takeaway

We used to think it took billions of years for galaxies to settle into their familiar spiral shapes. New data shows these mature shapes were already common just a billion years after the Big Bang, forcing us to rethink cosmic history.

From the abstract

Whether the "Hubble sequence" of galaxy morphologies exists up to z~4 is still disputed, and one of the challenges is characterizing galaxy structure consistently across a wide range of redshifts. To enable a fair comparison across cosmic time, we constructed "absolute" images of galaxies spanning 0.15<z<4.5 and 8<log $M_{\star}$<11 from HST CANDELS and JWST CEERS surveys, by matching the effective resolution and surface brightness limit of galaxies, accounting for cosmological dimming and evolu