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New Details From Cassini's Phoebe Flyby
No_Weak_Heart writes "New details and images of Cassini-Huygens' close encounter with Saturn's moon Phoebe have been released. Much of the data seems to confirm the earlier suspicion that Pheobe was formed in the outer reaches of the solar system and was later captured by Saturn's gravity. More coverage at Nature, NY Timesand the BBC. We covered the flyby here."
Not that anybody's going to read this topic, but here's the answer. Cassini does take both color and grayscale photos. Just like in any other environment, color requires more data and more processing. The majority of Cassini's photos are grayscale because they're easier and faster to take. There will be some color pictures once the data is processed and released, but there's more grayscale pictures and it's easier to get them out faster. And it's not like Phoebe is a colorful object anyway.
Strictly speaking, the spacecraft doesn't have a color camera. Rather, all of its cameras can be equipped with filters for various wavelengths - red, green, blue, infrared, ultraviolet, and so on. Taking a color picture requires multiple exposures through different filters, so it takes longer and delivers less resolution.
Finally, color pictures really aren't that valuable for science anyway. They make for pretty pictures and posters, but that isn't Cassini's job. Filtering at different wavelengths is important for some objects (particularly Titan and the rings), but for other objects, grayscale images usually convey very close to 100% of the scientific information that a color picture would.