For each night's observations, they added all the spectra they collected together to obtain an average spectrum for the star, and then subtracted this average spectrum from each observation.

ECONOMIST: Extrasolar planets

Several monster planets have been discovered by looking for the wobbles in a star's spectrum caused by a planet's to-and-fro tugging of its parent.

ECONOMIST: Twinkle, twinkle, giant planet

But some theorists believe that when it is possible, they will be able to determine how a particular object formed by comparing its spectrum with that of its parent star to determine the relative proportions of heavy elements in the two bodies.

ECONOMIST: Twinkle, twinkle, giant planet

Salman Khan is that rare Bollywood star who has a huge fan following across the vast spectrum of Indian society.

BBC: The controversial Salman Khan