Dark Spot at "Derain Crater" (Enhanced Absolute Natural Colors; credits for the additional process. and color.: Dr Paolo C. Fienga - Lunexit Team)

In the center of this image is Derain, an impact crater first viewed during MESSENGER's 2nd Mercury flyby and named in 2009.

Derain has material within it and in its surroundings that is much darker than the neighboring terrain. In fact, the material associated with Derain appears to have the lowest reflectance yet identified on Mercury's Surface.
The Dark Deposits may be material with a mineralogical composition different from the majority of Mercury's visible Surface, but more data are needed before any further insight into the composition can be gained.

Observations to be acquired during MESSENGER's orbital mission phase will help to identify the uncommonly Dark Material at Derain Crater and similar occurrences elsewhere on the Planet.

Also visible in this image (upper right side), is the rayed Crater "Berkel", which has Dark Material as well in its center and in a ring immediately surrounding it. In contrast, two neighboring craters of Berkel have bright rays but lack Dark Halos. Why do some craters contain Dark Materials while others do not? MESSENGER's orbital data will be used to investigate that question and to improve our understanding of the nature and structure of Mercury's Crust.

Date Acquired: October 6, 2008
Instrument: Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS)
Scale: Derain Crater is approx. 190 Km in diameter (such as about 118 miles)