Thanks in part to an instrument created by MIT Lincoln Laboratory, NASA’s
Earth Observing-1 (EO-1) spacecraft is sending back stunningly detailed
images of the planet.
Since its launch in November, EO-1, flying in formation with the Landsat
7 satellite, has taken more than 350 images. Comparing the images from
Landsat 7 and EO-1 allows researchers to evaluate EO-1’s land imaging
instruments.
The primary instrument on EO-1 is the Advanced Land Imager (ALI), designed
and developed at Lincoln Lab. One of three imaging instruments on board,
ALI is the first Earth-observing instrument to be flown under NASA’s New
Millennium Program.
One of two new Earth-orbiting missions, EO-1’s primary focus is to develop
and test ALI and other advanced land imaging instruments. The goal is to
demonstrate that a smaller, lighter, cheaper spacecraft can provide equal
or better images than Landsat.
Uses for the new technology include land use studies, mineral resource
assessment, coastal processes research and climate change studies.
Images from Landsat have helped researchers understand, for instance,
why Africa’s freshwater Lake Chad has been disappearing over the last
30 years.
Scenes of Alaska taken by ALI in the panchromatic band are of considerably
better quality than the panchromatic band image taken by Landsat 7 under
nearly identical lighting and surface conditions. ALI, which uses novel
wide-angle optics and a highly integrated multispectral and panchromatic
spectrometer, provides more resolution, sensitivity and dynamic range
than the comparable instrument on Landsat 7, NASA reports.
“A fully operational ALI may reduce the size and power requirements of
future Landsat-type instruments by a factor of four to five,” said Costas
Digenis, associate leader of the Advanced Space and Concepts Group at
Lincoln Lab and ALI program manager.
TESTING AND IMPROVING
Scientists and engineers at Lincoln Lab are evaluating the detailed
technical performance of the ALI.
In parallel, a team of Earth scientists assembled by NASA is assessing
the quality of the science products obtained and comparing results
directly with those obtained from Landsat 7. These investigations will
provide critical input for the design and implementation of the next
generation Landsat imager.
The NASA Goddard Space Flight Center has overall responsibility for the
EO-1 mission. Lincoln Lab developed ALI with New Millennium Program
instrument team members Raytheon Santa Barbara Remote Sensing for the
focal plane system and SSG, Inc. of Wilmington, MA for the optical system.
Lincoln Lab was responsible for the design, fabrication and test of the
instrument, as well as development of the software and databases for
calibration, and is also responsible for the initial on-orbit performance
assessment.
In 1996, NASA started the New Millennium Program to identify, develop and
try out instrument and spacecraft technologies that may allow new or more
cost-effective approaches to conducting science missions. Future NASA
spacecraft are expected to be smaller, lighter and less expensive than
current versions.
EO-1 is the first of three New Millennium Program Earth-orbiting missions.
For more on EO-1, see http://eo1.gsfc.nasa.gov .
IMAGE CAPTIONS: [http://web.mit.edu/newsoffice/tt/2001/mar14/imager.html]
[Image 1]
A panchromatic view of Yuma, AZ and the Colorado River made by the Advanced
Land Imager.
[Image 2]
A multispectral image of Oahu made by the Advanced Land Imager.