Aliens On Earth.com Resources for those who are stranded here UFOs | Paranormal | Area 51 People | Places | Random Top 100 | What's New Catalog | New Books Search... for keyword(s)   in Page Titles in Book Title/Author in Contents of Pages ---other searches--- Metacrawler Yahoo FAST Search Google Altavista Dogpile Inference Find Northern Light IWon.com MSN Search Las Vegas Sun Our Bookstore is OPEN Mothership -> UFO -> Updates -> 1998 -> Feb -> Here

From: NASANews@hq.nasa.gov
Date: Thu, 12 Feb 1998 14:42:43 -0500 (EST)
Fwd Date: Thu, 12 Feb 1998 22:39:10 -0500
Subject: NASA Radar Reveals Hidden Remains at Ancient Angkor

Douglas Isbell
Headquarters, Washington, DC                    February 12, 1998
(Phone: 202/358-1753)

Mary Hardin
Jet Propulsion Laboratory, Pasadena, CA
(Phone: 818/354-0344)

RELEASE: 98-28

NASA RADAR REVEALS HIDDEN REMAINS AT ANCIENT ANGKOR

    New evidence of a prehistoric civilization and remnants of
ancient temples in Angkor, Cambodia, have been discovered by
researchers using highly detailed maps produced with data from an
airborne imaging radar instrument created by NASA.

    Experts say the findings, made possible by the Airborne
Synthetic Aperture Radar (AIRSAR) developed by NASA's Jet
Propulsion Laboratory (JPL), Pasadena, CA, may revolutionize the
way archaeologists view the ancient city's development.

    Angkor is a vast complex of some 1,000 temples covering about
100 square miles of northern Cambodia.  Little is known of the
prehistoric occupation of this fertile flood plain, but at its
height the city housed an estimated population of one million
people.  The famous temples were built from the eighth to
thirteenth century AD and were accompanied by a massive
hydrological system of reservoirs and canals.  Today, much of the
civilization of Angkor is hidden beneath a dense forest canopy and
is inaccessible due to poor roads, land mines and political
instability.

    "The radar data have enabled us to detect a distribution of
circular 'prehistoric' mounds and undocumented temples far to the
northwest of Angkor," said Dr. Elizabeth Moore, Head of the Art
and Archaeology Department at the School of Oriental and African
Studies at the University of London.  "The site's topography is
highlighted by the radar, focusing our attention on previously
neglected features, some at the very heart of the city.

    "The radar maps not only bring into question traditional
concepts of the urban evolution of Angkor, but reveal evidence of
temples and earlier civilization either absent or incorrect on
modern topographic maps and in early twentieth century
archaeological reports," she said.

    "The radar images make apparent many features that are not
readily identifiable on the ground," said Dr. Anthony Freeman, a
radar scientist at JPL who has collaborated with Moore for the
past three years studying the use of radar on the Angkor site. 
"We can see differences in vegetation structure and some features
that are obscured by vegetation cover."

    In December 1997, Moore surveyed a small mound on the
perimeter of the famous 12th century AD temple, Angkor Wat, that
Freeman had first noticed in the radar image.  "Previous
archaeological accounts from 1904 and 1911 note only two temples
and make no mention of the distinct circular form of the mound. 
We found four to six temple remains, including pre-Angkorean
structures," Moore said.  "This suggests occupation of the 12th
century site some 300 years earlier, radically changing accepted
chronologies of Angkor."

    Angkor's beauty is seen in its temples, but the greatness of
the Khmer city lies in the multitude of water-related
constructions, according to Moore.  The Khmer kings nominally
dedicated temples to Hindu and Buddhist deities, but the
underlying significance was veneration of ancestral spirits,
ensuring fertility of the land.  Management of water was
essential, both for control during the monsoon rains and
conservation during the dry season and involved the construction
of moats, dikes, canals, tanks, and reservoirs.  The largest of
these reservoirs, dated to the 12th century AD, is five miles long
and its function remains a matter of archaeological debate.

    "These new detailed topographic maps have shown us many more
hydrological features and highlighted how they function in the
rituals and daily life of the Khmer people," Moore explained.

    "Using a technique known as radar interferometry, which
combines two images to create a three-dimensional topographic map,
we can construct a map of the area surrounding Angkor that is more
accurate than most maps we have of the United States," said Dr.
Scott Hensley, a radar engineer at JPL.  "This map lets us see
both natural and human-made water management features at the site
with great clarity."

    "Angkor is situated on the edge of the Tonle Sap lake, a
unique body of water that doubles in size during the rainy season. 
These maps give us new insights into the human impact on this
ecosystem, from the ancient Khmer to the present day, and are of
importance in the study of our changing Earth," Freeman continued.

    The Angkor radar images were taken in late 1996 as part of the
AIRSAR Pacific Rim Deployment and were a follow-up to the 1994
study of Angkor with data collected by the Spaceborne Imaging
Radar-C/X-band Synthetic Aperture Radar (SIR-C/X-SAR) that flew on
NASA's Space Shuttle Endeavour.

    Like SIR-C/X-SAR, AIRSAR transmits and receives three radar
frequencies in both horizontal and vertical polarizations.  While
both systems use C-band and L-band wavelengths, AIRSAR has the
added benefit of P-band, a longer wavelength that can penetrate
below the forest canopy.  In addition, AIRSAR can be flown in a
mode called TOPSAR that allows it to measure topography and create
three-dimensional images of the surface.

    AIRSAR images of the Angkor region will be posted to the
Internet at this address:

            http://www.jpl.nasa.gov/news/

    AIRSAR flies on a NASA DC-8 aircraft that is managed at NASA's
Dryden Flight Research Center, Edwards, CA.  The AIRSAR instrument
is managed by JPL, a division of the California Institute of
Technology, for NASA's Office of Earth Science, Washington, DC. 
This office manages NASA's Earth Science enterprise, an
internationally coordinated effort to study natural and human-
induced changes in the Earth's land, oceans, atmosphere, ice and
life.

    The AIRSAR flight over Cambodia was funded by the Government
of Thailand.  Ground verification has been made possible by Vann
Molyvann, Minister of State for Culture and Fine Arts, Territorial
Management, Urban Planning and Construction; and Dr. Ang Choul=8Ean
of the Cambodian Authority for the Protection and Management of
Angkor and the Region of Siem Reap.

                       -end-