Page 206 - Intro to Space Sciences Spacecraft Applications

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After the spacecraft is declared operational, the support personnel and
systems continue to monitor it for health and operability. Meanwhile, the
operations support system has begun to utilize the spacecraft and support
this use. This includes ground transmit and receiving stations and data col-
lection, reduction, and dissemination systems.

Spacecraft Design and Construction

Depending on the originator of the spacecraft idea, design and construc-
tion may occur in many different locations. Some experimental systems
may be the product of university-associated laboratories, such as the Johns
Hopkins Applied Physics Lab (APL), and the California Institute of Tech-
nology’s Jet Propulsion Lab (JPL). The National Aeronautics and Space
Administration (NASA) may create some of its own spacecraft at any of
its diverse locations, such as the Goddard Space Flight Center (GSFC) or
Kennedy Space Center (KSC). Preliminary military space system design
may occur at the Air Force’s Space Division or the Navy’s Space Systems
Activity (SPAWAR). But, in most cases, operational spacecraft will be
designed and built by industrial facilities based on requests for proposals
(RFPs) presented by the activity desiring the spacecraft to be built.

Launch Sites and Vehicles

After a spacecraft has been built and tested, it is transported to the
launch site to be mated with the launch vehicle for delivery into space. In
the United States, the two main launch sites are the eastern test range
(ETR) at the Kennedy Space Center in Florida and the western test range
(WTR) at Vandenberg Air Force Base in California. Airborne launches
from diverse locations have also become available.
Table 8-10 lists the total launch vehicle launch weight, lift-off thrust,
and maximum payload weight to a typical low altitude orbit for some
select launch vehicles. All numbers are approximate.
As indicated earlier, launch vehicles are designed simply to deliver
their payloads into space and are usually not capable of reaching the final
orbits from which many systems operate. Therefore, upper stages may be
used to position the spacecraft into (or close to) its operational orbit. As
mentioned before, most spacecraft have an associated propulsion system
which is used for final positioning and possible repositioning, but the