Beyond the answers - interesting background to this quiz

A family name written in Hollywood history

Jon Voight won the Academy Award for Best Actor for his role in Coming Home and later earned nominations for Runaway Train and Ali. His daughter Angelina Jolie grew up to become an Oscar-winning actress herself, taking home the Best Supporting Actress award for Girl, Interrupted. The pair even appeared on screen together, playing father and daughter in Lara Croft: Tomb Raider.

Two novels that defined teenage rebellion

F. Scott Fitzgerald's The Great Gatsby captured the Jazz Age's glitter and its emptiness, while J.D. Salinger's The Catcher in the Rye gave voice to adolescent alienation through narrator Holden Caulfield. Both books became staples of American school curriculums. Fitzgerald's novel was not a big seller during his lifetime, but it is now considered one of the great American novels.

The chemistry behind an ancient metal

Lead's chemical symbol, Pb, comes from the Latin word plumbum, which also gave us the word "plumbing" - fitting, since Roman water pipes were made of lead. The metal is soft, dense and was once common in paints and petrol, though its toxicity led to widespread bans. Its symbol is a reminder that chemical shorthand often preserves old languages.

Why Mars looks red

Mars owes its rusty colour to iron oxide - essentially rust - in its soil and rocks. That reddish tint made the planet stand out to ancient observers, and many cultures linked it to war and bloodshed. Its two tiny moons, Phobos and Deimos, are named after the Greek personifications of fear and dread.

The ocean that surrounds a frozen continent

The Southern Ocean encircles Antarctica and is recognised by many geographers as the world's fourth-largest ocean. It is home to powerful currents, including the Antarctic Circumpolar Current, which flows around the continent and helps isolate it climatically. Its cold, nutrient-rich waters support penguins, seals and vast swarms of krill.