Misc: In 1959 ---------- reveals an intense radation belt around the Earth. ?

Questions

In literature, who were the 'star-crossed lovers'?

In Louisa May Alcott's 'Little Women', which march sister dies?

In maritime history, a type of large, seagoing warship propelled by oars and, more frequently, by sail?

In mathematics, famous theorem which has led to important discoveries in algebra & analysis?

In medicine, the determination of the nature of a disease?