Enabling Moon-based Radio Cosmology - CosmoCube (24-25)

CosmoCube has been conceived to revolutionise current 21-cm cosmological observations of the Dark Ages and the Cosmic Dawn with a cubesat orbiting the Moon. With many launch opportunities expected in the near future, our approach makes strategic use of cubesats as they allow us to adopt a rapid, iterative approach to the quietest location in the Solar System while it is still pristine. The cubesat deploys a precision radiometer to measure spectral distortions in the Cosmic Microwave Background imprinted in the first 1 Gyr of cosmic time. Observed at 1 to 200 MHz, these frequencies are heavily saturated on Earth by radio interference, both natural and human, as well as electromagnetic interactions between radio antennas and their environment (eg. the soil underneath the antenna). The EDGES experiment reported in 2018 the detection of an absorption feature at redshift 17, well beyond the range of any other telescope. This finding has spurred multiple ground-based follow ups (eg. REACH) and several proposed lunar orbiters and even a prototype instrument on the recent Chang-e 4 mission. Now, lunar-bound ride-share opportunities, ideal for cubesats, open the door to rapid development in this arena.

After an initial UKSA NSTP grant to start the development of the on-board payload spectrometer in 2022, and a UKSA Category B Bilateral project to develop the mission concept, CosmoCube saw very rapid development through its participation in the University of Portsmouth Space Mission Incubator (CDF) before the summer. This project aims at developing technology and techniques to enable moon-based radio cosmology with CosmoCube and similar missions. In particular the project will tackle 4 main challenges: the development of the science payload, the development of the temperature stability and control systems, the development of an appropriate foreground removal technique and the development of an advanced mission design.