Colloquia

Earlier this summer, the pulsar timing array community announced strong evidence for the presence of a stochastic background of nanoHertz frequency gravitational waves. This has been the primary goal of the community for the past two decades, and it took thousands of hours of telescope time, over 500,000 pulse arrival times from ~70 millisecond pulsars, and a highly sophisticated and very computationally demanding analysis effort to accomplish. While we can't yet say for certain what is causing the gravitational waves, our best guess is a population of slowly merging super-massive black hole binaries throughout the universe. But it is possible that the signal also heralds new physics. So what does it all mean and what are we expecting next? And what other cool things can we do with all of this high-precision pulsar data?