Qualla: Hydrogen Epoch of Reionization Array

Hydrogen Epoch of Reionization Array: Introduction

Mon, 09 Mar 2026 00:00:00 GMT

Somewhere in the Karoo, 350 dishes made of wood, wire mesh, and PVC pipes stare straight up at the sky. They cannot move. They cannot take pretty pictures. What the Hydrogen Epoch of Reionization Array does instead is something no other instrument on Earth has been optimized to do: it listens for the faintest radio signal in the universe, a whisper left behind by the very first stars.

Hydrogen Epoch of Reionization Array: The Cosmic Dark Age

Mon, 09 Mar 2026 00:00:00 GMT

For hundreds of millions of years after the Big Bang, the universe was dark. Hydrogen gas filled space in a cold, featureless fog, absorbing the fading glow of the cosmic microwave background. Then the first stars ignited, and their ultraviolet radiation began tearing electrons f...

Hydrogen Epoch of Reionization Array: Why the Karoo

Mon, 09 Mar 2026 00:00:00 GMT

The frequency band HERA uses overlaps with FM radio, television broadcasts, and countless other terrestrial transmissions. In most places on Earth, these signals would drown the cosmological whisper completely. The Karoo desert near Carnarvon, South Africa, offers something vanis...

Hydrogen Epoch of Reionization Array: An Unconventional Design

Mon, 09 Mar 2026 00:00:00 GMT

Most radio interferometers spread their antennas to maximize unique baselines, producing sharp images of individual objects. HERA does the opposite. Its dishes are packed into a hexagonal grid, deliberately creating many identical baselines whose signals can be stacked to amplify...

Hydrogen Epoch of Reionization Array: Measuring the Unmeasurable

Mon, 09 Mar 2026 00:00:00 GMT

HERA will not produce glossy photographs of ancient galaxies. The cosmological signal is too faint and the foreground too overwhelming for that. Instead, the telescope will measure the power spectrum of hydrogen fluctuations across cosmic time, detecting statistical patterns in h...

Hydrogen Epoch of Reionization Array: A Stepping Stone to the SKA

Mon, 09 Mar 2026 00:00:00 GMT

HERA is one of four precursor instruments for the Square Kilometre Array, the most ambitious radio telescope ever planned. Alongside MeerKAT in the same Karoo park, and the Australian SKA Pathfinder and Murchison Widefield Array in Western Australia, HERA tests technologies and r...