James Turrell is a talented artist who works with light and colour, his most famous works are often done through the use of framing skies.
What is amazing about this piece is that the manipulation of the colours tricks you into thinking that the sky is changing colour. It is a fascinating illusion to observe and happens as a result to your eyes adjusting to the colours which are being presented so boldly inside the room. As the sun sets, the effect is at it's most powerful.
A YouTube video of the piece can be found below.