Time machine: The Thermopolis specimen of Archaeopteryx, recently X-rayed at a Stanford University particle accelerator to reveal previously unseen details of soft tissues.
Credit: Stephan Schulz
CHICAGO: High-powered X-rays from particle accelerators are helping researchers unlock the mysteries of dinosaurs and ancient documents in three dimensions, say scientists.
Gone are the days when researchers had to dig objects up and crack them open, reported experts this week at the American Association for the Advancement of Science's (AAAS) annual meeting in Chicago, USA.
The X-rays show detail non-invasively, which is important for looking at artifacts that are too fragile to excavate, explained Jen Hiller, a speaker at the conference and a scientist at Diamond Light Source, a research company on the Harwell Science and Innovation Campus in Oxfordshire, England.
Massive improvement
Synchrotrons were developed for high-energy physics research, but are now allowing scientists to look at the two- and three-dimensional (3-D) structure of fossils, old documents, and works of art.
"These X-rays work a thousand times better than what you could do with a commercial X-ray machine – only a synchrotron can do this," said Uwe Bergmann, a scientist at the Stanford Synchrotron Radiation Lightsource of Stanford University in California, USA.
Synchrotron X-rays are different from regular X-rays in that they are generated from high-speed electrons as they race around the ring of a particle accelerator, which makes them more powerful and concentrates them into a hair-thin beam.
When used to scan a fossil or other artifact, the rays can even illuminate some of the chemical elements they are made up of, such as calcium or phosphorous.
With the technique, experts can now see chemical elements from the original organism still present in fossils – a remarkable breakthrough.
Infancy of the technique
"What you normally can't see are the chemical elements from the original organism that might still be present in the fossil," said Bergmann. "Using X-ray fluorescence imaging, we can bring these elements to light, getting a better look at the fossil and learning more about the original animal."
A few weeks ago, a fossil of the species Archaeopteryx, a transitionary species between dinosaurs and their bird descendents, was scanned at the Stanford facility. This has allowed experts to see previously unseen details of the fossil, including soft tissue that once surrounded the bones.
"This is the very infancy of this new scientific method," commented palaeontologist Peter Larson of the Black Hills Institute in Hill City, South Dakota. "We don't even know enough about this to know the right questions to ask yet. All of a sudden, we can look at fossils in a very different and new way."
The method can also be used to illuminate writing on ancient parchments.
In another study at the Stanford facility, the technique was used to reveal the ink of hidden text beneath paint on a mediaeval copy of a treatise by Ancient Greek mathematician, Archimedes.
Earlier this year, parts of an obscured score by the Italian composer Luigi Cherubini (1760 to 1842) were discovered after the document was scanned. Following the X-ray, "the researcher was able to look right through the ink and read the score," said Mary Miller, a Stanford preservation librarian. "I think he was thrilled."
"The synchrotron is like a time machine," added Francesca Casadio, a chemist at the Art Institute of Chicago, who was also present at the AAAS meeting.
