The existence of the Cosmic Microwave Background was predicted some years before it was discovered in 1965. Since then, it has been mapped in great detail by a succession of dedicated probes. I will discuss how and why it exists as well as what it means for our understanding of the universe. Whilst detection of gravitational waves from relatively close inspiral events has been occurring since 2015, it was just last year that the presence of ultra-low frequency gravitational waves was confirmed. I will explain how the Murriyang Parkes radio telescope played an important role in finding evidence of background gravity waves, which are thought to have originated from the mergers of super massive galaxies.