Environmental Engineering Reference
In-Depth Information
Table 9.1.
Current and future types of constellation missions and possible issues
Type
Application
Typical design/
Data acquisition Operations
manufacture
Simple
University
Very low cost.
Not a major
Extremely low
(varied
sponsored.
Minimally
issue. Low rate.
cost. University
number of
Corporate
space-rated
May operate
level
satellites)
R&D
components
at amateur
radio frequencies
Cluster:
Coordinated
Complex.
Not a major
Similar to single
Cluster II (4),
science.
Satellite
issue. Typically
large satellite.
Magnetospheric Virtual
crosslinks.
high rate due to
Multiple
multiscale (5)
telescopes.
Extensive
science mission,
satellites
Stereo
testing
but number of
performing
imaging
required. High
satellites is
acoordinated
redundancy
limited or
function. Added
within
downlink access
effort for
satellites
can be controlled mission
Coverage-
Commercial
Satellites
Large number
May involve
Constellation:
phone/paging/ operate
of satellites
hundreds of
Globalstar (48), Internet
independently,
using many
passes per day.
Orbcomm (36), systems. Earth designed for
ground sites
Ideal for
TIROS (5),
(or planetary) mass production
concurrently.
automation, as
NASA
observation
with limited
Dedicated
there are many
NanoSat (100)
(multi-point
redundancy,
antenna sites
nearly identical
data
high duty cycle
may be needed
passes. Space
collection,
due to identical
comm architecture
broad survey
satellites working may be needed to
or coverage)
continuously
be fully networked
Military/
Inspection,
New concepts are
Only a few
Mostly orbit/
Tactical:
imagery
for very small,
satellites active
maneuver and
XSS-10,
low-cost, mass-
at a time. May
data-acquisition
ESCORT,
produced spacecraft use portable
activity.
Orbital Express
with no redundancy data acquisition
Data are
and minimal
sites. May have
for immediate
mission durations
a video downlink use only. No
plus minimal
long-term
status info.
trending, etc.
possess significant, and perhaps obvious, advantages over using just one or two
spacecraft. For example, NASA's proposed magnetotail constellation (MC)
mission, which will use a fleet of 30+ nanospacecraft, would offer space-physics
scientists the ability to perform 100 concurrent observations over the magne-
tosphere, allowing conditions and events recorded to be correlated spatially
and temporally.
Constructing and launching constellations will introduce many new and
significant challenges. For example, building, launching, and then properly
deploying as many as 100 spacecraft housed on one launch vehicle into their
required orbits will require the development and demonstration of new space-
craft control solutions so that mission operations costs associated with sup-
porting a constellation comprising a large number of spacecraft do not spiral
out of control.
