Description
The “Dark Ages” of the Universe, spanning redshifts z ~ 30–250, remain one of the last unexplored frontiers in observational cosmology. This pre-stellar epoch, rich in neutral hydrogen, offers a pristine view into the formation of structure, the properties of dark matter, and early cosmic evolution. The redshifted 21-cm hyperfine transition from this period encodes a wealth of information, but is inaccessible to ground-based instruments due to ionospheric distortion and pervasive radio frequency interference (RFI) below ~45 MHz.
CosmoCube is a UK-led space mission concept designed to overcome these limitations. It proposes a precision-calibrated, low-power radio radiometer operating from a low-cost satellite platform in lunar orbit. The spacecraft will conduct deep, RFI-free observations from the Moon’s far side, enabling detection of the sky-averaged 21-cm signal across 5–100 MHz (corresponding to z ~ 13–285).
The mission integrates heritage from the REACH experiment with novel hardware developments, including a deployable wideband antenna, a compact RFSoC-based spectrometer, and a thermal-stable calibration system. Data will be analysed using advanced Bayesian pipelines to isolate the cosmological signal from strong astrophysical foregrounds.
CosmoCube offers a timely and cost-effective opportunity to deliver the first direct constraints on the Dark Ages, with potential implications for the Hubble tension, dark matter-baryon interactions, and the physics of the early Universe. We present the mission architecture, science goals, instrumentation status, and the roadmap to flight in the current decade.
