The First Billion Years, According to JWST

TL;DR

JWST has profoundly advanced our understanding of the Universe's first billion years by providing unprecedented imaging and spectroscopic data, leading to new discoveries and raising important questions about early cosmic evolution.

Contribution

This paper summarizes the significant progress made in understanding the early Universe using JWST data, highlighting recent discoveries and future research directions.

Findings

Revealed detailed structure of early galaxies

Identified new phenomena in the first billion years

Rewritten aspects of cosmic evolution models

Abstract

With stunning clarity, JWST has revealed the Universe's first billion years. The scientific community is analyzing a wealth of JWST imaging and spectroscopic data from that era, and is in the process of rewriting the astronomy textbooks. Here, 1.5 years into the JWST science mission, we provide a snapshot of the great progress made towards understanding the initial chapters of our cosmic history. We highlight discoveries and breakthroughs, topics and issues that are not yet understood, and questions that will be addressed in the coming years, as JWST continues its revolutionary observations of the Early Universe. While this compendium is written by a small number of authors, invited to ISSI Bern in March 2024 as part of the 2024 ISSI Breakthrough Workshop, we acknowledge the work of a large community that is advancing our collective understanding of the evolution of the Early Universe.