 Troy Launay ending that report by Rebecca Murrell, and you can find more on that expedition on the science pages of our website. Before we go, a reminder of our main news at the moment. International allies have expressed support for Joe Biden after further high-profile gaffes raised more doubts about his fitness to seek re-election as US president. Stay with us if you can. We'll have a new summary in just a moment. I'm Jackie Leonard, and you've been listening to The Newsroom.