Scientists have developed a novel computer simulation to predict the observations of the Square Kilometer Array Low-frequency (SKA-Low) telescope as it searches for signals from the universe's earliest epochs, specifically aiming to directly observe the Cosmic Dawn and the Epoch of Reionization.

Detecting signals from these early cosmic events is technically challenging due to their extreme faintness, which is thousands of times weaker than the foreground noise generated by our galaxy and other sources.

To address these challenges, the simulation incorporates a wide range of radio source brightness, from extremely bright galaxies to emissions that are a million times fainter, ensuring realistic modeling of interstellar and extragalactic interference.

The Cosmic Dawn, which occurred between 200 and 600 million years after the Big Bang, marks the first appearance of stars, transitioning the universe from a dark age of neutral hydrogen gas to one where detectable radio signals are emitted.

During this period, neutral hydrogen emitted faint radio signals at a wavelength of 21 centimeters, which have since been redshifted to lower frequencies that modern radio telescopes can detect.

Following the Cosmic Dawn, the Epoch of Reionization saw early stars emitting ultraviolet light that ionized surrounding hydrogen, creating bubbles of charged particles that significantly altered the universe's structure.

This simulation is critical for developing methods to effectively isolate the faint signals from significant foreground interference, which is essential for accurate observations of these early cosmic events.

The SKA's exceptional sensitivity is expected to enable unprecedented spectral and spatial observations of the Cosmic Dawn and Epoch of Reionization.

Once operational, the SKA-Low telescope will be the most sensitive low-frequency radio telescope ever built, specifically designed to detect these elusive early universe signals and capture detailed measurements of hydrogen emissions during reionization.

The findings from this simulation underscore the potential of the SKA-Low telescope to provide unprecedented insights into the universe's first light sources and the processes that shaped its early structure.

Led by Anna Bonaldi from the SKA Observatory, the simulation includes various components such as the Cosmic Dawn signal, powerful radio sources, and measurement errors, providing a comprehensive testing ground for signal extraction techniques.

The simulation created by Bonaldi and her team also accounts for elements that real observations will encounter, including bright radio sources, emissions from the Milky Way, and atmospheric and calibration errors.