What is that light on the mountain?

The green portion of the solar spectrum as it scans from red to violet.

During the last year or so we have been asked this question many times. We have been testing a special art installation called Sunstar, created by Liliane Lin and John Vallerga. It is on loan to Mount Wilson Observatory, and is now being presented as part of Pasadena’s AxS Festival: City as Wunderkammerer.

Sunstar, directable prism array.