These high resolution images of space scenes are matted to perfection on quality card-stock board and feature a description of the image on back.
From NASA's Mars Reconnaissance Orbiter, we have this image that shows sand ripples in Mars' Proctor Crater. From their study on Earth, and close-up examination by the MER rovers, we know that ripples are composed of fine sand.
Image property of NASA.
|All images © Astrolith Graphic Products, inc. and John C. Wittenberg unless otherwise identified.|