Seeing more, colourfully, from space
Australian researchers will play an important role as NASA takes a new look
at the earth from space.
NASA's latest satellite, the Earth Observing-1 satellite, set for launch in
May, will contain the 'Hyperion' imaging equipment the first of its kind in
space and a pioneer of a new period of advanced imaging.
"Hyperion is an experiment with a new technology for space, which will
provide us with a much greater range of information about the earth's surface,"
says Dr David Jupp, head of CSIRO's Earth Observation Centre.
CSIRO and the Australian Centre for Remote Sensing (ACRES) have been selected
to participate in one of the ten Science Teams, drawn from research institutes
around the world, in the NASA experiment.
Scientists from NASA, and TRW Inc the American company that built Hyperion
are currently visiting key sites in Australia, some of them very remote, to be
used in the experiment.
According to Dr Jupp, Hyperion is unique because it will 'see' the earth from
space in 220 different spectral bands like different colours, but ranging from
visible light to infrared. Other earth observation satellites currently in
operation see up to only seven spectral bands. This 'Hyperspectral' imaging
(meaning 'many spectral bands') has until now only been achieved from aircraft
or from the ground.
"Current satellites measure only broad bands of colour on earth. Hyperion
will see much more," says Dr Jupp. "For example, Hyperion will be able to
distinguish 10 different shades of red, where a current operational satellite,
such as Landsat, will see only one shade of red. It will also be able to see
bands of light that the human eye cannot.
"Being able to measure such detail allows us to determine the composition of
rocks and soils, the types of algae or other pollutants in water or even the
component types of tree in a forest," says Dr Jupp. "We may even be able to map
the water content of leaves or the level of stress in trees, which would tell us
about the state of forests in much more detail than is possible with current
satellites."
CSIRO researchers will also help TRW Inc to test that the instrument is
working properly during the first 60 days of its flight. They will help with the
important task of calibrating the instrument by comparing Hyperion's readings
from five Australian test sites with measurements collected from the ground and
from aircraft.
"Everybody using the data from Hyperion will need to know how to correct its
readings for factors like the effect of the atmosphere," says Dr Jupp. "We need
to make sure that Hyperion sees the same shade of red, for example, that we
would see if we looked ourselves or measured it from the ground.
"We're in an excellent position to provide this information for NASA," says
Dr Jupp. "Australia has a wonderful variety of landscapes to test the instrument
on, from Lake Argyle in WA, which appears dark from space, to the bright glare
of the Strzelecki desert.
"We also have a long history of data from past and present CSIRO research
with which to compare the readings, so that we know if the instrument in
functioning properly," he says.
"Hyperion is the first hyperspectral sensor on a satellite," says Dr Jupp.
"Over coming years, such satellite-based sensors will provide a unique, detailed
perspective of large parts of the globe. Among these will be the Australian
Resource Information and Environment Satellite (ARIES) Hyperspectral satellite
which will be similar to, but more advanced than, Hyperion."
Hyperspectral imaging works because all substances create an often unique
spectral 'fingerprint' which can be captured by instruments like Hyperion. From
this 'fingerprint', specific substances can be definitively identified,
including pollutants, minerals, various components of trees and even corals
beneath shallow water.
The Earth Observing-1 satellite will be the first in NASA's New Millennium
Program Earth Observing series of satellites to be launched.
Dr Steve Ungar from NASA and Drs Jay Pearlman and Carol Segal from TRW
will be touring the Australian sites from February 7 to 12th. They
are available for comment in Canberra on the 10th and 11th
of February via David Jupp at (02) 6216 7203.
More information, pictures: Dr David Jupp 02-6216 7203 E-mail:
David.Jupp@eoc.csiro.au
Janelle Kennard 02-6216
7157
http://www.eoc.csiro.au/hswww/
To display a larger version of the image above clickhere.
Researchers from NASA will visit several of the sites in Australia that will be examined by the new instrument to ensure that it is functioning properly. They'll get a taste of some Australia's more remote areas, like Tinga Tingana, near SA's Lake Eyre.
To display a larger version of this image clickhere.
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