The first color image of Comet 67P/Churyumov-Gerasimenko has been released, and it’s about as colorful as you would expect.
“As it turns out, 67P/C-G looks dark grey, in reality almost as black as coal,” says OSIRIS Principal Investigator Holger Sierks.
Rosetta scientists used red, green and blue wavelength filters to produce the image above. Superimposing the images as the comet races towards the sun and the Rosetta spacecraft orbits the comet is no easy task. Getting the images lined up accurately is the reason why it took so long for the first color image of Comet 67P.
An earlier image of the comet showed it had a reddish color. This is due to the comet reflecting red light slightly better than other wavelengths according to the ESA.
The solid grey color did surprise ESA scientists. It points to zero differences across the climate surface. Ice, for example, would appear blue in a color image. The consistent color indicates the surface is covered by some sort of dust. Philae encountered this same layer of dust when it drilled into the comet’s surface last month.
Next up for Rosetta? Figuring out what makes up the dust covering the comet’s surface. To do that, scientists will use the OSIRIS imaging system onboard Rosetta. Combinations of OSIRIS’ 25 filters will be used to look for minerals, and various gases.
Here’s a bonus mosaic image released today by the ESA. It was taken just over 20km away from the comet and is made up of four images.