Nuit Blanche is a 1 night festival that happens in Toronto every year. It starts at sundown and finishes at sunrise. This year they have a 'Global Rainbow' installation by Yvette Mattern.
Here is a copy and paste about the exhibit.
Global Rainbow is poetic, magical and powerful. A high specification laser light projection beaming in parallel horizontal lines creates a natural perspective horizon arc simulating a natural rainbow arc with a trajectory of up to 60 km.
From Chinatown to one of Toronto's most iconic buildings, the CN Tower, Global Rainbow blazes through Toronto’s night sky. It encompasses the skyline and its viewing perspective is as ephemeral as viewing a natural rainbow. This monumental installation is visible from all exhibition areas. As a powerful and luminescent symbol of peace and hope, it embraces geographical and social diversity.
Global Rainbow follows in the tradition of several art movements in the late sixties and early seventies; and draws on similarities to land and sky arts monumental landscape projects. It literally "paints the sky" with seven simple but distinctly powerful lines of colour representing the rainbow spectrum to create an artwork that is performative, sculptural, painterly, and minimalist in form.
Yvette Mattern is a New York and Berlin based visual artist whose work has an emphasis on video and film, which frequently intersects performance, public art and sculpture. Her ongoing monumental laser light installation: Global Rainbow has been presented for monumental events since 2009, such as the London 2012 Cultural Olympiad, in Berlin and New York City. Mattern aims to connect all demographics in a beautifully engaging experience. She sees her work as a visual translation of hope and peace.
Nikon d7100, 50mm 1.4. 10 sec f2.8