Workers apply foam and molds on the shuttle Atlantis' external tank to areas damaged by hail. The white hole with a red circle around it (upper right) is a hole prepared for molding and material application. The red material is sealant tape so the mold doesn't leak when the foam rises. The white/translucent square mold is an area where the foam has been applied and the foam has risen and cured against the mold surface. Credit: NASA/George Shelton.
