Researchers plan to use the moon's static orbit to study the universe's "dark ages." Their small satellite will search for ancient hydrogen signals and cosmic clues. Astronomers hope to reveal insights about the "cosmic dawn" by deploying a small spacecraft designed to orbit the far side of the moon to detect "ancient whispers" from space.

Artistic rendering of the British-led Cosmic Cube detector. The probe will orbit the far side of the moon and listen for "ancient whispers" from the early universe. Image credit: Nicolo Bernardini (SSTL Ltd) and Kaan Artuc (University of Cambridge)

The purpose of this mission is to explore the early days of the universe shortly after the Big Bang, when space was dark and devoid of stars and galaxies.

However, exploring this cosmic "dark age" requires an environment free of distractions. Earth is full of atmospheric disturbances and electronic noise, posing a huge challenge to catching such weak radio signals.

A model of the Cosmic CubeSat undergoes thermal vacuum testing at the Royal Aeronautics and Space Laboratory (RAL Space) facility. Image credit: Dr Will Granger, Royal Aerospace Laboratory

Dr Eloy de Leila Acedo, who made the suggestion at the Royal Astronomical Society's 2025 National Astronomy Meeting in Durham, said: "It would be like trying to hear a whisper at a loud concert next door."

This makes it very difficult to receive weak signals from billions of years ago. In order to detect the special radio signal from hydrogen, the earliest, most basic, and most abundant chemical element in the early universe, we need it to be quiet. "That's why we propose to launch a small satellite to orbit the moon and detect signals that could provide clues about how everything started and how structures like galaxies eventually formed."

The British-led CosmoCube mission aims to operate from the far side of the moon, where the lunar body will act as a massive barrier to radio interference from Earth.

Located in this quiet region, the spacecraft will be able to "listen" to "ancient whispers" and collect valuable data about the universe's Dark Ages and Cosmic Dawn - eras that remain largely unknown in modern cosmology.

A depiction of the Dark Ages of the universe, after the Big Bang and before the first stars and galaxies formed. Image source: University of Colorado Boulder

de Lera Acedo, head of radio astronomy and cosmology at the University of Cambridge's Cavendish, said: "In doing so, CosmoCube aims to help us better understand how our universe transformed from a simple, dark state to the complex, light-filled universe we see today, which contains all the stars and galaxies. Crucially, it will also help scientists study mysterious dark matter and its role in shaping the structure of these universes."

CosmoCube will feature a finely calibrated low-power radio radiometer mounted on an affordable satellite platform designed to orbit the moon. The instrument operates at a lower frequency (10-100 MHz) and is specifically designed to detect extremely weak radio signals hidden in background noise.

One of the mission's goals is to investigate the Hubble tension—the persistent inconsistency between the rate of expansion of the universe measured from the early universe and that inferred from recent local observations.

Additionally, the data collected could shed new light on dark matter-baryon interactions (non-gravitational interactions between dark matter and ordinary matter) and deepen our understanding of the physics of the early universe.

This so-called "dark age" is one of the last unexplored frontiers in observational cosmology. The period before stars are born provides original insights into the formation of cosmic structure, the nature of dark matter, and the evolution of the early universe.

"These radio waves travel incredible distances and now they are also carrying information about the history of the universe," said CosmoCube researcher Professor David Bacon of the University of Portsmouth. "The next step is to go to the quieter side of the moon and get the message."

The Cosmo Cube is supported by the UK Space Agency's Science Bilateral Program and is being developed by a UK-led international consortium with researchers from the Universities of Cambridge, Portsmouth and STFC RAL Space.

Instrument development is well underway, with functional laboratory prototypes and environmental testing underway, as well as key collaboration with industry partners such as SSTL Ltd to develop space platforms and mission concepts.

The project team is planning a four- to five-year launch roadmap with the goal of reaching lunar orbit by 2020.

Compiled from /scitechdaily