Infrared imaging has been used to gather information about historical objects and to help in their preservation and restoration.
The Star Spangled Banner
When Francis Scott Key saw the American flag flying over Fort McHenry in Baltimore in 1814, he was inspired to write the words to what is now the national anthem of the United States of America, "The Star Spangled Banner."
The flag, assembled by piecing strips of loosely woven English wool bunting together, was stitched by a maker of ships’ colors and signal flags named Mary Pickersgill, who was assisted by her 13-year-old daughter, two nieces (ages 13 and 15), and a 13-year-old African American indentured servant.
Wool is a protein like hair. When it gets moist and is exposed to sunlight and oxygen, the fibers deteriorate and get split ends. Using infrared spectroscopy, researchers were able to identify the organic compounds in small fiber samples from the flag, and study the material's chemical changes over time, which contributed to their understanding of how to best preserve the flag known as the "Star-Spangled Banner."
Advanced infrared imaging systems, together with highly sensitive electronic cameras and computer image-processing technology, have helped researchers reconstruct parts of ancient historical texts from mere fragments.
NASA researchers working on the Dead Sea Scrolls have been able to uncover and reconstruct age-blackened sections of the texts, where the carbon-black ink had become indistinguishable in visible light from the age-blackened background of the parchment. In infrared light, the ink stands out clearly from the parchment background, allowing the researchers to read the otherwise invisible text. The Dead Sea Scrolls are religious texts, written around 2000 years ago, that are helping historians to chart the rise of Christianity in the region. They were discovered in caves in Judea in the 1940s, and are considered some of the most important finds in modern archaeology.
Published: 02 August, 2013