What is the average color of the universe? Our Earth, being a beautiful blue orb, has an overall perceived wavelength of somewhere near 470 nm, that being the wavelength of light blue, because the oceans play an enormous role in the weighted average of all of the Earth's colors.

But what about the whole universe? The Earth is nothing in comparison to the host of multicolored stars, ranging from deep red to fiery blue. Taking into consideration the number of stars and each separate color's weighted average,  could we calculate the average color of the universe?
According to astronomers at Johns Hopkins University, it's beige. Note, they previously announced it was turquoise, but they identified a bug in their calculations, redid the numbers, and now it was determined the average color is beige. Kind of boring, yes, but kind of what you'd expect.

In short, they collected "detailed light measurements from more than 200,000 galaxies. They then constructed a "cosmic spectrum," which represents all the energy in the local universe emitted at different optical wavelengths of light" and averaged it. More details at link below.

NPR : The Color of the Universe Is...