Instant Genius The hunt for the first stars in the Universe
Oct 12, 2025
Dr. Emma Chapman, a Royal Society Research Fellow and astrophysicist at the University of Nottingham, delves into the enigma of the Universe's first stars. She explains how they emerged from the Big Bang, igniting the cosmos from darkness. Emma highlights their massive, hot nature, and short lifespans ending in supernovae. Discover how discoveries from the James Webb Space Telescope have reshaped our understanding, revealing unexpectedly massive early galaxies. Lastly, she emphasizes the importance of studying these primordial stars for insights into the cosmos.
AI Snips
Chapters
Books
Transcript
Episode notes
What Physically Defines A Star
- A star is a massive collection of gas that collapses under gravity until nuclear fusion ignites at its core.
- Fusion produces heat and light, marking the birth of a star.
From Big Bang To Cosmic Dawn
- After the Big Bang the universe cooled and entered a Dark Ages with only hydrogen and helium present.
- Gas collected along a dark-matter web and the densest clouds ignited as the first stars, ending the dark ages.
Why First Stars Were Much More Massive
- First-generation stars formed from pristine hydrogen and helium, so cooling was inefficient and clouds grew far more massive.
- As a result, early stars were typically ~100 solar masses, hotter and bluer than most stars today.
