If you are in London between now and September 27, 2015, visit the Covent Garden Market to see the pop-up art installation executed by French artist Charles Pétillon, an expert in creating balloon structures. The installation, titled Heartbeat, consists of 100,000 white balloons pulsating with light. The 54-metre long and 12-metre wide structure can be seen stretched across the roof of the market&rsquos South Hall. This is Pétillon&rsquos first balloon sculpture display outside France. With Heartbeat, the artist wanted &lsquoto represent the market building as the beating heart of this area &ndash connecting its past with the present day to allow visitors to re-examine its role at the heart of London&rsquos life&rsquo. The sculpture is part of Covent Garden&rsquos annual cultural programme. There will also be a pop-up gallery in the piazza showcasing his previous work.