IMAGE First Light
June
5, 2000 -- "First-light" pictures from NASA's Imager
for Magnetopause to Aurora Global Exploration (IMAGE) spacecraft
have revealed the global ebb and flow of hot, electrified gas
(plasma) around the Earth in response to the solar wind. Severe
disturbances in this region controlled by the Earth's magnetic
field (the magnetosphere) are capable of disrupting satellites,
telephone and radio communications, and power systems.
"IMAGE is the first weather satellite for space storms,"
said Dr. James L. Burch, Principal Investigator for IMAGE at
Southwest Research Institute, San Antonio, Texas. "This
revolutionary spacecraft makes these invisible storms visible.
In a sense, IMAGE allows us to view the Earth through plasma-colored
glasses. We eagerly anticipate the arrival of severe solar weather
associated with solar maximum, which we are now entering."
Above: This picture, recorded by IMAGE's Extreme Ultraviolet
Imager, shows solar ultraviolet radiation scattered from ionized
helium in the Earth's extended atmosphere. The ionized helium
envelope is 2 to 3 times the size of the Earth. Irregularities
at the fringe of the image (upper left) indicate magnetic storm
activity. This is the first time such features have been imaged.
This is a selected frame from a sequence which is available as
a 1.6
Mb Quicktime movie.
Previous spacecraft explored the turbulent magnetosphere by detecting particles and fields in the immediate vicinity of the spacecraft. This technique limited their vision to small portions of this vast and dynamic region, which extends beyond the Moon on the Earth's night side.
"The old way of tracking magnetic storms is like trying to understand severe thunderstorms in the Midwest by driving around with a rain gauge out the window," said Dr. Thomas Moore, IMAGE Project Scientist at NASA's Goddard Space Flight Center, Greenbelt, Md. "With IMAGE, we will see the big picture, just like entire storm systems appear on the evening news with weather satellites."
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The first pictures from IMAGE were presented at a press conference during the spring meeting of the American Geophysical Union May 31 in Washington, D.C.
"These first images are an enticing glimpse at the spectacular results expected from IMAGE once we encounter really heavy weather in space," said Dr. James Green, Deputy Project Scientist for IMAGE at Goddard.
All
spacecraft systems have been successfully deployed and are operating
normally. All scientific instruments
are operating as expected and are returning images.
The Radio Plasma Imager instrument provides a three-dimensional
view of the plasmasphere by sounding it with radio pulses, like
an ultrasound image of the human body. To accomplish this, it
uses the longest antennas ever deployed in space, longer than
the height of the Empire State Building.
Left: The Radio Plasma Imager (RPI) on IMAGE is the
first-of-its-kind instrument designed to study the dynamics of
the magnetosphere by using radar techniques. In order to generate
very low frequency radio waves and to receive the resulting echoes,
RPI uses very long dipole antennas. IMAGE has 2 spin-plane dipole
antennas (along the spacecraft X and Y axis) and one spin-axis
dipole antenna (along the spacecraft Z axis). The X and Y axis
antennas are 1647 ft or 500 meters tip-to-tip each. These antennas
are 182 ft longer than the height of the Empire State Building,
making the IMAGE spacecraft the largest dipole antenna system
currently in space. This is a selected frame from a sequence
which is available as a 100
kb Quicktime movie.
A suite of three Neutral Atom Imaging instruments is recording
the glow of fast atoms coming from throughout the Earth's magnetic
field. This reveals the shape and motion of the clouds of plasma
that make up a magnetic storm.
The Far Ultraviolet Imaging instrument
is collecting the first-ever images from space of the Earth's
proton aurora. The aurora, commonly known as the northern and
southern lights, is a ghostly light show seen most often at high
latitudes of Earth. The dance of lights that is visible from
the ground is caused by electrons striking and lighting up the
atmosphere much like electricity lights up a television screen.
The proton aurora is invisible to the naked eye and has never
been viewed from space; from the ground, it is visible only in
far-ultraviolet wavelengths.
Right: Aurora are caused by the interaction of precipitating
charged particles (electrons and ions) with the neutral gases
of our atmosphere. Light from the Earth's aurora occur principally
in two oval-shaped bands lying between ~65 and 75 degrees magnetic
latitude and centered on the northern (aurora borealis) and southern
(aurora australis) magnetic poles. IMAGE observes the aurora
in several important wavelengths and has captured its first geomagnetic
substorm (pictured above). These observations are caused by precipitating
electrons. This is a selected frame from a sequence which is
available as a 145
kb Quicktime movie.
Southwest Research Institute manages the IMAGE project and leads the IMAGE science investigation. The IMAGE Principal Investigator is James L. Burch.
Web LinksIMAGE First Light Movies and Pictures - from NASA/GSFC
IMAGE home page - from the Southwest Research Institute
IMAGE home page
- from NASA/GSFC
More
Science@NASA stories about IMAGE:
Innovative
Space Weather Mission Nears Launch -- Feb. 24, 2000
The RADAR Cop in Space --
March 24, 2000
Space Weather Satellite Blasts Off -- March 27, 2000
