Beyond the answers - interesting background to this quiz

Why Mercury looks older than almost everything else

Mercury's surface is considered the most ancient among the planets because it has changed very little since the early solar system. Unlike Earth, it has no plate tectonics to recycle its crust, and its extremely thin exosphere provides almost no weathering. The heavily cratered terrain we see today is essentially a fossil record from billions of years ago, shaped mainly by volcanic activity that ended long ago and by countless impacts.

The speed of light is not just a number

The speed of light in a vacuum, 299,792,458 metres per second, is not simply a fast velocity. It is a fundamental constant of nature, built into the structure of modern physics. The metre itself has been defined using this speed since 1983, meaning the number is exact by definition. It also acts as a cosmic speed limit: no object with mass can reach it, and light always travels at this speed regardless of how the observer moves.

Alexander Graham Bell and the race to the telephone

Alexander Graham Bell received the US patent for the telephone in 1876, but the story is more crowded than a single name suggests. Elisha Gray filed a caveat for a similar device on the same day, and Antonio Meucci had been developing voice-transmission ideas years earlier. Bell's patent survived legal challenges, and his successful demonstration - famously calling his assistant with the words "Mr. Watson, come here" - secured his place in the popular history of communication.

Venice, once known as La Dominante

Venice earned the nickname La Dominante because of its long dominance over Mediterranean trade and its powerful navy. For centuries the Republic of Venice controlled key routes between Europe and the East, building an empire that included coastal territories and islands far beyond its lagoon. The name reflects not just wealth but political influence: at its height, Venice was one of the most formidable states in Europe.