Night light: Spectra Barcelona, a light sculpture by Japanese artist Ryoji Ikeda, shines above the Spanish city to coincide with the Sonar electronic music festival

At first glance, it looks like Barcelona is being visited by aliens - with a powerful and other-worldly shaft of light beaming down from a bright object in the heavens.

But it is actually the handiwork of Japanese artist Ryoji Ikeda.

The effect is achieved by Ikeda concentrating 64 separate beams of light so that they slightly fan out into the night sky.

The interaction with clouds above the Spanish city means that the display is constantly changing.

Ikeda calls his work Spectra Barcelona, and gives it the rather more lofty title of light sculpture. 

He has shone similar beams from Nagoya Castle in Japan, Vondel Park in the Netherlands and Paris.

Barcelona's beam was arranged to coincide with the city's electronic music festival, called Sonar.