|
Peruvian Frozen Treasure
"We
appreciate the excellent support and attention which we received
from EdgeTech, and look forward to close relationships in the future
on both conventional and unconventional projects. …"
--Dr.
Charles Bullock
Engineering Fellow
Carrier Corporation
The
Background
The use of cutting-edge technology has proven valuable in the preservation
of a five hundred year old Inca mummy, literally frozen in time.
A volcanic eruption in Peru sent tons of ash to the nearby snow-covered
mountain, Nevado Ampato. The Peruvian sun warmed the dark ash, melting
centuries of packed snow and ice. Subsequently, mountain climbers
discovered the mummified body of a 13 to 14 year old girl, who had
been ceremoniously sacrificed to the mountain god. The "Ampato
Maiden" had been left high up on a 20,700 foot mountain. However,
unlike most previously discovered mummies, the Inca girl’s
body, was preserved in superb condition. Once the Maiden was brought
down from the mountain, attention immediately turned to learning
more about this Peruvian treasure.
Scientists
painstakingly removed the mummy’s wrappings to reveal the
perfectly preserved body of the young girl, complete with hair,
skin, organs, and even body fluids intact. But in order to conduct
further studies both in Peru and in the United States, scientists
would have to develop a way to preserve the biological and genetic
structure of the frozen mummy.
The
Challenge
Over 500 years old and frozen, the mummy is particularly fragile.
Moreover, to ensure longevity, the mummy must stay frozen. Scientists
needed a portable refrigeration unit that would not only reliably
keep the mummy frozen but also eliminate the possibility of sublimation
(the process of ice evaporation). If the Inca girl were to melt
or undergo sublimation, she would wither away, and along with it,
the world would lose rare genetic and historical secrets.
Because
of the unique circumstances, there were no stock environmental chambers
that would fit the need. Scientists determined that they required
a solution that could guarantee absolute control over temperature
and humidity.
The
Solution
Racing against time, the National Geographic Society asked The Carrier
Corporation, Farmington, CT, the world leader in refrigeration and
cooling systems, to design and build an environmental cooling chamber
that would meet the stringent requirements of high humidity, but
at a low temperature.
According
to the Maiden’s discoverer, the unit must consistently maintain
a temperature of 10 to 20º F, and a Relative Humidity of between
85 to 90%.
The
design called for a well insulated, triple paned glass case super
cooled by a modified refrigeration unit. Carrier recognized the
importance of an accurate humidity measurement. If the RH dropped
below the specification, the Ampato Maiden would dry out. Therefore,
reliability and accuracy was needed for the control system to work
properly. Carrier used an available ten year old EdgeTech Model
200 DewTrak chilled mirror transmitter. The Model 200 was integrated
into the one-of-a-kind environmental chamber. The patented DewTrak
provides a primary dew point measurement that is used to control
the conditions for the chamber. Being a fundamental measurement,
chilled mirror does not experience hysteresis (measurement memory)
in the unusual conditions of high humidity and low temperatures.
With the Model 200 in place, the weight of the mummy soon stabilized
and control was Carrier’s.
Today,
the refrigeration unit is on permanent display in Peru and features
the technology of a Carrier-designed environmental chamber, controlled
by an EdgeTech Model 200 DewTrak dew point transmitter. With the
past protected, the future looks bright. Sometimes you have to look
forward to see the past.
| 
