See the Milky Way's Sagittarius A* black hole in an amazing polarized Event Horizon Telescope image

Image of the supermassive black hole Sagittarius A* (Sgr A*). from the Event Horizon Telescope (EHT) collaboration "has ...

Measuring the expansion rate of the universe - Hubble constant tension explained

Learn how Hubble is measuring the expansion rate of the Universe in this new explainer from NASA's Goddard Space Flight ...