You may've seen this picture before. From the Hubble Legacy Archive, it captures one of the most stunning galactic collissions we've found: lower-right-in-the-picture NGC 4039's encounter with lower-left-in-the-picture NGC 4038. (The images are stunning, but not, alas, the names.) And here, too, the colors the organges and lavenders and reds of the image seem especially dramatic.
But why do we color certain images we get from space? And why do we choose those colors? Writing yesterday at io9, Esther Inglis-Arkell explained:
[A]ccurate information can't be shown any other way than with false colors. Astronomers observe visible light, sure, but they also look at ultraviolet, infrared, and radio waves, none of which can be seen by humans, but all of which can be translated into visible light. At first, these images are often rendered in black and white, but to make them both dramatic and clear, they're translated into color. This is hardly faking anything. Radio transmissions aren't any color, so making them look good in vivid colors isn't any more false than giving people a bland black and white image.
Below, recent Pictures of the Day: