Environmental Engineering Reference
In-Depth Information
Fig. 1.1.
New Millennium Program (NMP) Space Technology 5 (ST5) spacecraft
mission (image credit: NASA)
ST5 was designed so that the satellites would be commanded individually
and would communicate directly to the ground. There was a 1-week period
of “lights out” operation where the microsats flew “autonomously” with pre-
programmed commands in a test to determine whether commanding could be
done onboard instead of from ground stations. In the future, this approach
would allow the spacecraft to react to conditions more quickly and save on
ground control costs. Preprogrammed commands are considered only as a
step toward autonomy and as a form of automation, since the commands are
not determined by internal goals and the current conditions of the spacecraft
software.
1.1.2 Solar Terrestrial Relations Observatory
The Solar Terrestrial Relations Observatory (STEREO) mission, launched in
March 2006, is studying the Sun's coronal mass ejections (CMEs), which are
powerful eruptions in which as much as 10 billion tons of the Sun's atmosphere
can be blown into interplanetary space [
37
]. CMEs can cause severe magnetic
storms on earth. STEREO tracks CME-driven disturbances from the Sun to
earth's orbit, producing data for determining the 3D structure and dynam-
ics of coronal and interplanetary plasmas and magnetic fields, among other
things. STEREO comprises two spacecraft with identical instruments (along
with ground-based instruments) that will provide a stereo reconstruction of
