Where Does the Sand Come From? Oct 10, 2017 nasaboy ⋅ NASA POTD, Space ⋅ NASA Pictures ⋅ No comments This image from NASA’s Mars Reconnaisance Orbiter (MRO) shows one possible place where sand grains are being produced on Mars today. Like 0 Thanks! You've already liked this 86 views Leave a Reply CancelYou must be logged in to post a comment. This site uses Akismet to reduce spam. Learn how your comment data is processed.