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$1.3 billion Terra is intended to be a stethoscope in the sky — a satellite that will
provide daily check-ups on the Earth’s health. The size of a small bus and weighing
10,500 pounds, Terra is the flagship of NASA’s Earth Observing System, which
eventually will comprise a flotilla of about 20 satellites. EOS is an attempt to carefully
and continuously monitor the entire Earth to evaluate the trends of global change. Terra
and other EOS instruments will measure global habitability, examining whether the current
number of people on Earth and their activities are sustainable. Running’s
involvement with NASA started in 1981 when the space agency broadened its research team to
include a more diverse group —even an ecologist in faraway Montana. Running and other
global change scientists helped guide NASA’s vision for a comprehensive Earth
monitoring system in the ’80s, and after EOS was conceived in 1990, Running’s UM
group was awarded a $7.9 million grant to design software for Terra.
Specifically, UM researchers crafted software for MODIS, the Moderate Resolution
Imaging Spectroradiometer, the primary sensor of five bundled into Terra. MODIS will
measure the atmosphere, land and ocean processes, ocean color, global vegetation, cloud
characteristics, temperature and moisture profiles, and snow cover. Orbiting from pole to
pole at an altitude of 705 kilometers, MODIS will scan the entire Earth every one to two
days, with the ability to hone in on details less than a kilometer wide.
Terra and other EOS satellites will monitor how rapidly carbon dioxide and other gases
responsible for global temperature change will accumulate in the future. The satellites
also will measure changes such as deforestation, desertification, glacial retreat,
wildfires, urbanization and more. Terra is a cooperative venture among many countries, and
Canada and Japan each provided one of Terra’s instruments.
Running assembled a talented team to help program MODIS. Glassy, a primary player,
personally wrote three of the problem-solving algorithms for the software. He said their
work is composed of 75,000 lines of code in C programming language.
“This was uncharted territory for all of us,” Glassy said. “We had to
create a brand new way of doing things, since this was the first time NASA had scattered
its work around the nation at various institutions. We constantly e-mail and call
researchers all over the place to bring everything together.”
He said the project was as much a technological and engineering challenge as a
scientific one. They had to design and assemble new hardware at UM that would allow them
to run local data-crunching processes after the satellite’s launch.
Glassy said their innovative and painstaking work should pay big dividends for Earth
science research. “This software will let us put a microscope on the Earth’s
ecosystems every day,” he said. “We will be able to estimate the productivity of
all land on the Earth.”
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