Another implementation that came to my mind was, there could be emotion sensors all around the memorial space. By detecting the overall emotion of the people around, such as anger, sadness, calmness, the tree lights could change color.
In The Future
I envision this installation as something that can bring people together. You hear about events that happen once a year, like a flower that blooms only for a week in the summer. It could become a culture of sorts, every year December 3rd people would gather around the tree and watch it bloom, and realize that the world hasn't forgotten the Bhopal Gas Tragedy of 1984.
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