‘Blueberry’ Layers Indicate Watery Origins

• Click the image above for a larger view
• Full-Res JPEG (1015 x 778) (146.7 kB)
• Full-Res TIFF (1015 x 778) (790.7 kB)

Caption:

This microscopic image, taken at the outcrop region dubbed "El Capitan" near the Mars Exploration Rover Opportunity's landing site, reveals millimeter-scale (.04 inch-scale) layers in the lower portion. This same layering is hinted at by the fine notches that run horizontally across the sphere-like grain or "blueberry" in the center left. The thin layers do not appear to deform around the blueberry, indicating that these geologic features are concretions and not impact spherules or ejected volcanic material called lapilli. Concretions are balls of minerals that form in pre-existing wet sediments. This image was taken by the rover's microscopic imager on the 29th martian day, or sol, of its mission. The observed area is about 3 centimeters (1.2 inches) across.

Cataloging Keywords: