Solar-powered LED 'firefly' lightbulbs took a trip down Tokyo's Sumida river in an event called the "Tokyo Firefly" on May 6.
Toyko's Sumida River has hosted firework displays for centuries, and now it has been used to facilitate the "Tokyo Firefly" event this week.
Thousands of solar-powered electric 'fireflies' floated down the river, lighting up the surface to an electric blue sheen. Over 100,000 bulbs that contained light-emitting diodes, measuring just three inches across and charged with solar-generated electricity were thrown into the river by participants and then later collected by nets further downstream.
The LED lights passed by the Tokyo Sky Tree, which opens later in the month -- decorated with lights and music for the event. The new, functional landmark in Tokyo required an initial investment estimated at 40 billion yen ($49bn). Impressive at 634 meters tall, the Tokyo Sky Tree's purpose is to act as a digital broadcaster as well as a 'disaster prevention' facility in the future by serving as an information relay network in case of emergencies, as well as relaying radio and television signals.
The festival is a modern take on "the age-old Japanese love of watching fireflies along waterways", CNet reports.