Why Two Satellites Improve Coverage

In the news show, flu season starts early in the Northern hemisphere due to pesky new strains, so will vaccines be effective? Also, the baby 'swim cap' which promises less invasive brain monitoring, and the European Space Agency's GPS powered satellites which are surveying the water cycle. Then, we find out the best way to shout at seagulls to stop them stealing our snacks... Like this podcast? Please help us by supporting the Naked Scientists