This January, the American Astronomical Society held its big annual meeting completely online. The Covid-19 pandemic ruled out the society’s planned gathering in Scottsdale, AZ but the AAS pivoted by opening-up digital access to thousands of astronomers across the United States and around the world. More than 3,000 registrants were listed in the online portal, thus demonstrating that the vital communication of astronomical research, education, and public outreach could carry on in this alternative format.
If the Big Bang theory is correct, how fast is the universe expanding? Astronomers are facing a troubling disconnect between different methods used to measure the expansion rate, known as the Hubble constant. The two methods are giving similar but slightly different rates. Either one method is providing inaccurate results, or there is some kind of unknown physics operating in the universe.
Galaxies comprise the largest self-gravitating systems of luminous matter in the universe, swirling masses of matter and energy just looking for trouble. Over the past few decades, astronomers have come to appreciate how fervently active galaxies can be. Besides hosting roiling clouds of intense starburst activity, they often also sport supermassive black holes in their centers that can pack a powerful punch. These myriad histrionics can affect the host galaxy's subsequent evolution and even the destinies of neighboring galaxies.