The protective gear worn by motorcyclists can be extremely hot and uncomfortable in sweltering Australian conditions. Does heat stress contribute to accidents, and how protective is safety gear anyway? Mark Horstman lays his mind and body on the line as scientists put motorcycle clothing to the test. Also, what did the beginning of time look like - that moment of creation? What are the biggest explosions in the universe like? We've never been able to observe these dramatic cosmic events in the past because they are invisible to all of our telescopes. But now, with the detection of gravitational waves, which Einstein predicted 100 years ago, that's about to change. Gravity waves are very different to light waves or radio waves, which today's telescopes detect: they are ripples in the very fabric of space-time itself. Now that they've been detected, scientists can start building a new kind of telescope that will pick up gravitational waves, rather than light or radio waves, and allow us to observe a whole host of new astronomical phenomena, including, one day, a glimpse of the big bang itself.