Researchers are planning to use a suitcase-sized satellite to explore the early universe by harnessing the radio silence of the moon’s far side, according to details published in Theguardian. The proposed CosmoCube mission aims to detect a faint radio frequency signal emitted by neutral hydrogen atoms more than 13.5 billion years ago.
CosmoCube Mission Targets the Early Universe
Prof Eloy de Lera Acedo, the lead author from the University of Cambridge’s Cavendish Laboratory, noted that the mission offers a compact, low-cost platform to probe the earliest parts of the universe’s history. The total cost for the project is estimated to be just under £50m, with a launch expected about five years from now. The Courthouse News has already granted more than £2m in funding toward the initiative, which is designed to operate for a duration of two years.
Overcoming Earth-Based Radio Interference
Detecting the targeted 21cm line—also referred to as the H-line—has proven exceptionally difficult using instruments based on Earth. In addition to the signal being extremely weak, researchers face obstacles including disturbances created by the Earth’s ionosphere and pervasive human-made technology, ranging from FM radios to plane communications and satellites.
While experts working at the EDGES (Experiment to Detect the Global EoR Signature) radio telescope in Australia previously claimed to have found the 21cm signal, questions have been raised regarding those results. By positioning CosmoCube in lunar orbit, the mission avoids terrestrial disruptions. Once in orbit, the small satellite will unfold a lightweight radio antenna to operate at extremely low frequencies between 10-50 MHz while repeatedly calibrating its instruments to distinguish genuine cosmic signals from internal electronic noise.
Probing Cosmic Temperature and Dark Matter
As the satellite passes the far side of the moon, it will track how the signal’s wavelength has been stretched, or redshifted, relative to the cosmic microwave background radiation. Researchers plan to use this data to monitor the physical temperature of gas during the early universe, which acts similarly to a thermometer.
This observation window spans from the start of the cosmic dark ages approximately 380,000 years after the big bang, through the cosmic dawn when the first stars and galaxies emerged, to the end of the epoch of reionization roughly 1 billion years after the big bang. Furthermore, investigators expect that the amplitude and shape of the 21cm signal will be influenced by dark matter, providing insights into how this mysterious component helped pull hydrogen together to form the earliest stars and galaxies.
A Race Against Lunar Traffic
Phil Bull, a professor of cosmology at the Jodrell Bank Centre for Astrophysics who is not involved in the project, welcomed the mission for its potential to clarify the processes that lit up the universe after the dark ages. However, Bull cautioned that CosmoCube faces competition from other planned lunar missions that might reach the milestones first.
Moreover, Bull warned that other lunar arrivals might carry the very type of human-generated radio noise that the mission seeks to escape, turning the endeavor into a race against time. To handle data once transmitted back to Earth, researchers intend to apply statistical methods to remove Milky Way radio emissions, while utilizing computer simulations and mission measurements to account for antenna-induced distortions.
