From the Website:
CosmoCube’s mission will open a brand new window onto the universe, allowing us to study a previously inaccessible region of the Universe’s history. The probe will launch to and orbit the Moon, a feat that has not yet been achieved.
When we look out into space, we’re also looking backwards in time. The incredibly faint radio signals that CosmoCube will detect originate from a period of time called The Dark Ages. This is before any stars or galaxies had formed in the universe, and so there is very little light to observe from that time. This mission will make use of intensity mapping of 21 cm emission from clouds of neutral hydrogen to study the history of the universe from about 380,000 years after the big bang through the first billion years of its evolution.
By escaping the loud and constant radio signals being produced on Earth, CosmoCube will collect data as it orbits the moon. When the satellite is closer to Earth, it will transmit data to the ground, and while it is on the far side of the moon CosmoCube will be able to detect signals from the incredibly distant universe.
Difficulties of Earth-based Observations
These observations need to be made using radio waves. On Earth, the atmosphere and human communications cause significant noise and interference with probes trying to make these observations.
Ground-based telescopes are significantly challenged by the noisy Earth - ionosphere, Radio Frequency Interference (RFI), and near-field soil emissions. They also need to remove/bypass foreground signals such as synchrotron emission from our own galaxy which can be up to 100,000 times greater than the 21 cm signal we are looking for.