| NASA Peers Into
Jamestown’s Past
NASA Langley — the research center famed for its
contributions to space exploration — has been using
its high-tech X-ray equipment to help Jamestown archeologists
peer centuries into the past.
Archeologists
with the Association for the Preservation of Virginia
Antiquities have pulled encrusted clumps from a Jamestown
well that’s 14 feet deep and nearly 400 years old.
They took the mysterious gunk to the NASA Langley Research
Center in Hampton, where Charles H. Greenhalgh Jr. X-rayed
them. NASA’s X-ray equipment is far more powerful
than X-ray machines commonly used in health care settings,
Greenhalgh explains. A dentist, for example, takes a
low-level X-ray in a fraction of a second, while Greenhalgh
exposes the Jamestown clumps to much higher concentrations
of radiation for up to one minute.
The
result is a clear picture of the artifacts inside the
clumps. “What’s really there is often so much
different from what the mass looks like,” Greenhalgh
says. The first clump of brick, clay and rusted iron
looked like a small cannon from the outside, but X-rays
revealed a funnel-shaped object that lacked the density
to be a cannon. Another clump that was completely indistinguishable
from the outside concealed the mechanism of a 17th-century
matchlock gun.
Besides
identifying the objects, the X-rays help archeologists
decide if the finds are worth conserving and what type
of cleansing treatment to apply — electrolysis
or air abrasion. So far, Greenhalgh has X-rayed about
50 artifacts, including tools, a gun barrel and pieces
of body armor. The archeologists have made it to the
bottom of the old well, but there will be more objects
to X-ray as the rediscovery project accelerates toward
Jamestown’s 400th anniversary in 2007.
While
Greenhalgh waits for the next clump to arrive from Jamestown,
he uses his X-ray equipment to inspect things such as
wind-tunnel models and aircraft parts. That may seem
centuries removed from Jamestown, but NASA scientists
are actually quite accustomed to peering into the past.
When they train their telescopes on Beta Centauri, they
are seeing the star as it appeared 490 years ago —
long before The Virginia Company set sail for the New
World.
—
Karl Rhodes
Return
to Virginia Business - January 2003
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