recent results from NANOGrav - the North American Nanohertz Observatory for Gravitational Waves - establish astrophysically significant limits in the search for low-frequency gravitational waves. This result provides insight into how often galaxies merge,and how those merging galaxies evolve over time. To obtain this result, scientists required an exquisitely precise, or nine-year pulsar-monitoring campaign conducted by two of the most sensitive radio telescopes on soil,the Green Bank Telescope in West Virginia and the Arecibo Observatory in Puerto Rico.
Source: phys.org