Salmonella outbreak, and Roman shipwreck discovery

Coming up, health agencies grapple with a Salmonella outbreak across Europe. What's behind it? Also, astronomers spot the fastest-moving star in the Milky Way, hurtling around the supermassive black hole at the heart of the galaxy; regulators in the United States have followed Europe's lead by approving an influenza vaccine that relies on mRNA technology; and we explore the remnants of Neapolitan…