Explanation:
What color is the universe?
More precisely, if the
entire sky were smeared out,
what color would the final mix be?
This whimsical question came up when trying to determine
what stars are commonplace in nearby galaxies.
The answer,
depicted above,
is a conditionally perceived shade of
beige.
To determine this, astronomers computationally averaged
the light emitted by one of the largest sample of
galaxies
yet analyzed: the 200,000
galaxies of the
2dF survey.
The resulting
cosmic
spectrum has some emission in all parts of the
electromagnetic spectrum, but a single perceived composite color.
This color has become much less blue over the past 10 billion years,
indicating that redder stars are becoming more prevalent.
In a contest to better name the color, notable entries
included skyvory, univeige, and the winner:
cosmic latte.
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