Lewis & Clark Revisited: Satellite Archeology Digs Out The Past
Reprinted with permission of Alex Philp & Space.com, January 10, 2002
The U.S. Congress made an Apollo-like decision nearly
200 years ago to dispatch an expedition of explorers into
uncharted territory. Back then the financial bar to probe the
unknown was a bit lower than the $25 billion needed to hurl
human adventurers to the Moon.
Two centuries ago, American President Thomas Jefferson
sought a paltry $2,500 in funds. In 1803, Congress did
allocate the money, footing the bill to send what Jefferson
later tagged as the Corps of Discovery into territory west of
the Mississippi River - beyond the western border of the United States.
Striking out the following year from St. Louis, Missouri, Meriwether Lewis and William
Clark led the 35-member band of intrepid surveyors on an arduous 19-month journey
into strange surroundings - to the Pacific Ocean and back. Meticulous journals were
kept. Landscape conditions were noted. Plant, animal life and aboriginal inhabitants,
as well as waterways were among items recorded - all for the history books.
Now thanks to a 21st century merger of remote sensing spacecraft, computer
technology and special software, the pioneering Lewis and Clark trail is once again
This on-going archeology from on high offers an enlightening high-tech flashback into
America's ecological past. In some cases, the pictures are not pretty.
Changing face of the West
The upcoming Lewis and Clark Bicentennial Commemoration will showcase the efforts
of NASA scientists and other researchers in a special project. These experts are
partnered to piece together satellite and aircraft remote sensing imagery in order to
create precision 3-D maps and visualizations of the Lewis and Clark trail and stopover
The result: A vast cache of satellite imagery along the Lewis and Clark trail can
become available to the Internet browsing public.
Landsat 5 and black and white historical aerial photo with Lewis and Clark trail line. Blend of
images show changes in Missouri River near Desoto National Wildlife Refuge North of Omaha.
IMAGE CREDIT: GCS Research
NASA's Stennis Space Center's Earth Science Applications Directorate in Mississippi
has been spearheading the work.
The data being assembled shows how the ecosystem has been altered over the last
200 years. For example, changes to river systems, the spread of invasive species,
and how sprawling populations have transformed the face of the West is being
charted. Moreover, the research can assist in historic and archeological studies of fort
sites and campsites along the Lewis and Clark Trail.
Snapshot in natural history
The trail project is underway through a NASA Space Act Agreement, engaging the
talents of GCS Research, a geospatial information technology company in Missoula,
Montana and the Montana State University (MSU) TechLink Center.
"With the upcoming bicentennial of the Lewis & Clark expedition, it seemed
appropriate that this data set be made available to researchers, educators, and the
public," said David Weston, Technology Manager of the MSU TechLink Center. NASA
and the Department of Defense fund the center to develop and commercialize
"The lasting value of the Lewis & Clark Corps of Discovery expedition is in the journals
and maps that they created. They represent a snapshot in the natural history of North
America, two hundred years ago. The NASA remote sensing data sets represent
another snapshot in time," Weston told SPACE.com. "Taken as a whole, the
collection will provide valuable insight into the growth, and changes of this nation, from
St. Louis to the Oregon coast," he said.
Weston said the architecture of the special web site is now being drafted, to be up
and operating early next year. As NASA's efforts continue, and more data is collected,
it is anticipated that the archive will grow throughout the bicentennial years, he added.
Twists and turns
Spotting Lewis and Clark encampment sites is not easy.
Like the trail itself, the research is full of twists and turns, made so by land cover growth and land use change over the
intervening period of time. By employing remote sensing and modern mapping technologies several tasks are underway.
For one, the accuracy of expedition maps drafted by William Clark can be appraised. Furthermore, land cover patterns
within areas of interest are being studied to identify high-probability locations of sites noted in the expedition’s journals
and maps. In addition, archaeological site integrity of important Lewis and Clark encampment sites for degradation and
destruction from land cover and land use change can be judged.
"What NASA wants us to do is take the data and build an interactive geo-imagery system," said Alex Philp, President
of GCS Research. Data collected will be made available to the public on the World Wide Web, free of charge, he said.
Slice through time and space
Exploring the geography of the trail via the Internet is not the only benefit. Viewers will also discover a sense of change
occurring across diverse American landscapes. "The focus will be the geography of change along the Lewis and Clark
trail," Philp said.
A key objective of GCS Research -- aided by tapping a host of existing partnerships and software products -- is to
enable easy public access to imagery data. The consortia of private sector firms can come up with cutting edge,
next-generation technology solutions for interactive web systems, Philp said.
"At the end of the day, we want the end user -- the teacher, the student, the researcher, the public -- to go to this portal
and get what you want, when you want it. That's the vision," Philp said.
By studying 200 years of change, embodied within that research are important messages from the past.
"I look at the trail as a transect through time…a slice through time and space," Philp said. "Through compelling
visualizations, I'm hoping people think about the stewardship…the preservation…the restoration of the environment," he
Taking a visual voyage
Philp admits that taking a visual voyage along the trail can be unnerving in some locales.
"There are parts of the trail that are very depressing. The urban transformations have been dramatic in some areas. At
the same time, there are areas, certainly not pristine, yet the degree of change is less," he said.
"So I think you get the full gamut of depression, concern, and outright outrage at the change. And then there are other
places along the trail where you have hope," Philp told SPACE.com.
The Lewis and Clark trail project is designed not only to help people understand the value of remote sensing and
NASA's mission of Earth observation. "I also want them to think about this concept of change," Philp said.
Ultimately, questions regarding environmental care, Philp noted, have to be addressed in a political arena. "They are
addressed from a value perspective. But I think there are places we can save. There are places we can restore. There
are places where we can understand what we've done."
Earth and Mars parallels
Looking into the future, Philp said, appreciating the saga of Lewis and Clark sets the stage for even bolder jumps into
terra incognita - unexplored land.
"The Corps of Discovery took the necessary equipment, collective skill set, and vision to go into an unknown world in
search of many things. The expedition redefined, literally, an understanding of the West and set the foundation for
colonization," Philp said.
Some NASA astronauts, Philp has been told, look to Jefferson's letter of instructions to Lewis as a guiding mandate
about what space colonization and Mars exploration will be as an experience.
"There are so many parallels," Philp said.
"Mars exploration and Lewis and Clark's Corps of Discovery represent analogous exploration and scientific analysis of
an unknown geography. Both efforts symbolize NASA's quest for scientific understanding about Earth and our
neighboring planet. When humans set foot on Mars, they will carry with them Jefferson's vision of understanding what
lies beyond the horizon."
Article written by Leonard David, Senior Space Writer with space.com. © 1999-2003 SPACE.com, Inc. ALL RIGHTS RESERVED.
Alex Philp is President at GCS Research (www.gcs-research.com)
and Director of the Geospatial Research Group, Department of Geography, The University of Montana