How does the Sun heat its corona?
How do rotation and mass-loss
affect the evolution of stars, and how big does a star have
to be in order to eventually explode as a supernova?
Why isn’t the supermassive
black hole at the center of the Milky Way giving off lots of
energy, like we see in quasars?
What are gamma ray bursts?
What is the history of star
formation in the universe? When were the first stars formed?