100,000 LED Spheres Flowing Down a Japanese River

The inaugural Tokyo Hotaru festival was held last weekend. And kicking off the festivities were an impressive display of 100,000 LED lights – made to resemble hotaru (fireflies) – that floated down the Sumida River through central Tokyo. Dubbed “prayer stars,” the LEDs were provided by Panasonic, who claims that the balls, which were
designed to light up upon contact with water, were 100% powered by solar energy. After illuminating a large stretch of the river, which also hosts a popular fireworks festival in the summer, the LEDs were all caught in a large net.

There are plenty of literary references indicating that the Sumida River was once home to real fireflies, which were said to gather around clean, running water. Searching for these luminous creatures on the banks was a popular activity in Tokyo (Edo, at the time) during the 18th century. For sad and obvious reasons, fireflies no longer inhabit the area. The Tokyo Hotaru festival is part of the city’s “Sumida River Renaissance” initiative.

Like fireflies? Check out these stunning long-exposure photos of fireflies by Japanese photographer Tsuneaki Hiramatsu. Then read the story about how they went viral.

As part of the recent Tokyo Hotaru Festival, 100,000 illuminated blue LEDs were released in the Sumida River. The massive installation of solar-powered spheres was meant to mimic a swarm of fireflies that twisted and bobbed along the river by moonlight. For those of you worried about pollution or safety, the lights were later caught downstream by giant nets

Written By Awais Ali