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The Experimental Cosmologist Hunting for the First Sunrise

September 20, 2023

To catch even a whiff of the universe’s earliest epochs — an age of darkness, and one of new light — Cynthia Chiang builds her own equipment. Then she deploys it at the ends of the Earth.

Four Years On, New Experiment Sees No Sign of ‘Cosmic Dawn’

February 28, 2022

When astronomers tried to confirm a signal from the birth of the first stars after the Big Bang, they saw nothing.

The Webb Space Telescope Will Rewrite Cosmic History. If It Works.

December 3, 2021

The James Webb Space Telescope has the potential to rewrite the history of the cosmos and reshape humanity’s position within it. But first, a lot of things have to work just right.

How the Cosmic Dark Ages Snuffed Out All Light

March 2, 2020

The recent discovery of some of the first galaxies in the universe illuminates the darkest era in cosmic history.

Whisper From the First Stars Sets Off Loud Dark Matter Debate

March 29, 2018

A surprise discovery announced a month ago suggested that the early universe looked very different than previously believed. Initial theories that the discrepancy was due to dark matter have come under fire.

Earliest Black Hole Gives Rare Glimpse of Ancient Universe

December 6, 2017

It weighs as much as 780 million suns and helped to cast off the cosmic Dark Ages. But now that astronomers have found the earliest known black hole, they wonder: How could this giant have grown so big, so fast?

Discoveries Fuel Fight Over Universe’s First Light

May 19, 2017

A series of observations at the very edge of the universe has reignited a debate over what lifted the primordial cosmic fog.

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A Seeker of Dark Matter’s Hidden Light

September 1, 2016

The astrophysicist Tracy Slatyer is searching for faint wisps of dark matter annihilating in the early universe — and perhaps in hiding places closer to home.

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