Unbelievable as it may seem, the two stars are the same color. They look different because the different background colors and stripes change our perception of their color.
Scientists are redefining the complex ways in which color is perceived—physically, by the eyes, yes, but color perception also takes place in the brain. So a particular color may not always be seen in the same way by different people or in different circumstances. Some scientists have suggested that color is not a property of an object at all, but only the way the object is perceived by an individual.*