His own star catalogue, the Historia Coelestis Britannica, was eventually published posthumously by his wife and co-observer at the Observatory, Margaret Flamsteed, in 1725.

BBC: A Point of View: Crowd-sourcing comets

So in 1712, Newton, by now president of the Royal Society, together with the indefatigable Halley, again obtained the data by subterfuge, and published a pirated edition of a new star catalogue.

BBC: A Point of View: Crowd-sourcing comets

The first Astronomer Royal, John Flamsteed, compiled the most accurate star catalogue of his day as part of this attempt (though the solution was eventually provided by John Harrison, a clock maker who designed a timepiece that was robust enough to withstand the rigours of sea travel, and was thus able to substitute for the stars in the relevant calculations).

ECONOMIST: Save the Royal Observatory!

The announcement that Bowie was releasing new material came as a surprise to many in the music world, and has had Bowie aficionados picking over the fiercely private star's back catalogue, comparing his early work with his latest release.

BBC: David Bowie album scores first number one in 20 years

Individual travellers seeking bespoke itineraries are on their own: there is, for instance, no catalogue or database of room prices for China's 4, 500 star-rated hotels.

ECONOMIST: E-business in China