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| Image above: The Delta II rocket with NASA's THEMIS
spacecraft aboard lifts off Pad 17-B. Photo credit: NASA |
Taking multitasking to new heights, NASA launched the five THEMIS satellites
aboard a single Delta II rocket from Cape Canaveral Air Force Station
in Florida at 6:01 p.m. EST.
Racing into space on the flaming power of three rocket stages and nine
solid rocket motors, the THEMIS satellites will soon disperse around Earth
to monitor auroras like the Northern Lights.
THEMIS stands for the Time History of Events and Macroscale
Interactions during Substorms. It is NASA's first five-satellite mission
launched aboard a single rocket. The spacecraft separated from the launch
vehicle approximately 73 minutes after liftoff. By 8:07 p.m. EST, mission
operators at the University of California, Berkeley, commanded and received
signals from all five spacecraft, confirming nominal separation status.
The mission will help resolve the mystery of what triggers geomagnetic
substorms. Substorms are atmospheric events visible in the Northern Hemisphere
as a sudden brightening of the Northern Lights, or aurora borealis. The
findings from the mission may help protect commercial satellites and humans
in space from the adverse effects of particle
radiation.
NASA is undertaking the mission to investigate what causes auroras in
the Earth's atmosphere to change in appearance and dissipate. Discovering
why the light of auroras can fluctuate and fade will provide scientists
with important details on how the planet's protective magnetosphere works
and on the sun-Earth connection.
The Mission
THEMIS is a mission to investigate what causes auroras in the Earth's
atmosphere to dramatically change from slowly shimmering waves of light
to wildly shifting streaks of color. Discovering what causes auroras to
change will provide scientists with important details on how the planet's
magnetosphere works and the important Sun-Earth connection.
THEMIS' satellite constellation will line up along the sun-Earth line,
collect coordinated measurements, and observe substorms during the two-year
mission. Data collected from the five identical probes will help pinpoint
where and when substorms begin, a feat impossible with any previous single-satellite
mission.
"The THEMIS mission will make a breakthrough in our understanding
of how Earth's magnetosphere stores and releases energy from the sun and
also will demonstrate the tremendous potential that constellation missions
have for space exploration," said Vassilis Angelopoulos, THEMIS principal
investigator at the University of California, Berkeley. "THEMIS'
unique alignments also will answer how the sun-Earth interaction is affected
by Earth's bow shock, and how 'killer electrons' at Earth's radiation
belts are accelerated."
The Mission Operations Center at the University of California, Berkeley,
will monitor the health and status of the five satellites. Instrument
scientists will turn on and characterize the instruments during the next
30 days. The center will then assign each spacecraft a target orbit within
the THEMIS constellation based on its performance. Mission operators will
direct the spacecraft to their final orbits in mid-September.
During the mission the five THEMIS satellites will observe an estimated
30 substorms in process. At the same time, 20 ground observatories in
Alaska and Canada will time the aurora and space currents. The relative
timing between the five spacecraft and ground observations underneath
them will help scientists determine the elusive substorm trigger mechanism.
Watch the THEMIS story
All
about the THEMIS satellites in a short video package
THEMIS Movie Trailer
View
Video (Windows)
View
Video (Real)
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