Color change illusion

"Into the sky"

The surround appears to be red when observers approach the figure while fixating at the center. In addition, the surround appears to move away and to rotate when observers approach the figure while fixating at the center

"Heat"

The rings appear to be red when observers approach the figure while fixating at the center, whereas they appear to be blue when observers move away from the figure while fixating at the center. For both cases, the rings appear to rotate in the different directions.