NASA's Dawn

This colorful composite image from NASA's Dawn mission shows the flow of material inside and outside a crater called Aelia on the giant asteroid Vesta. The area is around 14 degrees south latitude. The images that went into this composite were obtained by Dawn's framing camera from September to October 2011.
To the naked eye, these structures would not be seen. But here, they stand out in blue and red.

The crater has a diameter of 2.7 miles (4.3 kilometers). The exact origin of the flow structures is unknown. A possible explanation is that the impact that produced the crater could have created liquid material with different minerals than the surroundings.

The composite image was created by assigning ratios of color information collected from several color filters in visible light and near-infrared light to maximize subtle differences in lithology (the physical characteristics of rock units, such as color, texture and composition). The color scheme pays special attention to the iron-rich mineral pyroxene.


The Dawn mission to Vesta and Ceres is managed by NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, for NASA's Science Mission Directorate, Washington. The University of California, Los Angeles, is responsible for overall Dawn mission science.