Why did we develop the International Space Station in the first place? What have we learned in its 25+ years of operation? When is it coming down, and why? And what’s coming up next?
How do particle colliders work? What kinds of energies are we talking about? Are there any uses for colliders except for physics experiments?
What are some sources of gravitational waves that aren’t black holes? How did inflation create gravitational waves? How can we possibly detect them?
How do we measure the sizes of stars? What are the biggest ones today, and how big could stars have gotten in the past? Is there any way for a star to cheat and get even bigger?
What powers Cepheid variable stars? What about Mira variables and pulsating stars? And are there variable stars that don’t actually vary at all?