A 19-year-old worked out a dying star's mass limit during a boat trip to England

In 1930, Subrahmanyan Chandrasekhar sailed from India to study at Cambridge, and used the eighteen-day voyage to work out what happens to a star once it runs out of fuel. He calculated that any collapsing star heavier than about 1.4 times the Sun's mass can't settle into a stable white dwarf — it has to keep collapsing. Senior astronomers mocked the idea for years before it was accepted.

— Subrahmanyan Chandrasekhar, The Maximum Mass of Ideal White Dwarfs — Astrophysical Journal, 1931