Seen here we have started to encase the dinosaur footprints in what is known as a field jacket. A field jacket is much like a cast that a doctor would place on a broken arm or leg. Our field jacket consisted of many layers of burlap soaked in plaster-of-Paris into which we also laminate metal pipes to act like splints for additional support. Here Michael is working to remove the very hard sandstone layer below the iron-rich clay layer in which the prints were preserved. Photo taken on January 7, 2013. Credit: NASA/GSFC/Rebecca Roth NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram