-
____ is another term commonly used for a spacecraft primary structure
Bus
-
Three basic types of spacecraft structural elements used for support and load are columns. ____ & _____ and _____
- frames
- trusses
- structural plates
-
The favored shape used for the structures of early Soviet spacecraft was the _____
sphere
-
Vacuum effects on solid materials including metals can produce _________, which could result in the formation of "whiskers."
sublimation
-
Both solar wind and cosmic ray particles present potentially ______ effects on surface materials in space, including metals
erosive
-
Atomic oxygen that oxidizes metal surfaces in low-Earth orbit requires a ______ _______ for protection of spacecraft surfaces
durable coatings
-
Torques from external magnetic fields can be
minimized by avoiding __________ materials in the spacecraft.
ferromagnetic
-
Although the most abundant particles in space are extremely small, spacecraft _____ ______ and _____ can be significant over long periods of exposure
surface erosion and pitting
-
Charge buildup from ____ _____ and _______ makes careful grounding necessary for both metal and composite structures.
solar wind and radiation
-
One of the most effective spacecraft debris shields is not a thick, solid chamber walls, but a ________ _____ that disperses any impacting particle energy over a large area.
standoff shield
-
One of the serious disadvantages of using titanium for spacecraft structures is that it is difficult to ______.
machine
-
Many of the early American spacecraft, and even some today, employ an _______ shaped bus structure
octagonal
-
A spacecraft is subjected to high amplitude ______ and ______ loads during launch and its ascent phase
vibrations and acoustic
-
The greatest vibrational energy source on a spacecraft during its operation (launch through termination) is in the _____ phase
ascent
-
The vibrational frequency of an elongated structural element will be _______ if its length is increased
decrease
-
The vibrational frequency of an elongated structural element will be _______ if its mass is increased
decrease
-
The strength or amplitude of a resonant vibration in a structural element will ______ as the difference in the resonant frequency and the drive frequency becomes smaller (drive frequency approaches the resonant frequency).
increase
-
Can the amplitude of the vibrational
(drive) frequencies on a launch vehicle change with altitude?
Yes
-
The highest range in temperature range in the solar system is at/near the planet _______.
Mercury
-
The narrowest range of temperatures in the solar system is at/near the planet ______
Pluto
-
The temperature of a surface material with high emissivity would have a _____ temperature compared to material of low emissivity
lower
-
The temperature of a surface material with high absorptivity would have a ______ temperature compared to material of low absorptivity
higher
-
Temperature is a measure of _____ energy
heat
-
A temperature that has reached a relatively constant value is called _______ temperature
equilibrium
-
Kirchkoff's law suggests that a material with high emissivity (ɑ) also has ____ absorptivity (ϵ).
high
-
______ paint is an example of a coating/material has both high ɑ and high ϵ.
Black
-
Of the heat transfer mechanisms used on spacecraft, only ______ systems and ______ systems are used for heat removal.
passive and active
-
Except for heat pipes, _______ heat transfer is not significant on spacecraft because of the lack of gravity.
convection
-
____ radiates as a blackbody
Sun
-
According to the zeroth law of thermodynamics, heat always flows from ___ to ____
hot to cold
-
An active thermal control system uses ______ and/or ______ systems
mechanical and or electrical
-
The most extreme temperatures are moderated by a spacecraft's ______ thermal control system components.
passive
-
The most extreme heat source in the inner solar system come from ____.
sun
-
The approximate energy available from solar radiation in the visible and IR at 1 AU is approximately _____ W/m2
1340
-
At Mars (1.52 AU), this would be approximately ___ W/m2
590
-
Heat energy radiated from a surface is proportional to the equivalent temperature of the surface to the ____ power.
4th
-
One of the most common surface coatings for spacecraft radiators is Z___.
306
-
A heat pipe is an example of a _______
thermal control system
passive
-
The approximate lowest temperature available on a spacecraft using radiative cooling is __K.
60
-
The Space Shuttle used ______ for the cooling fluid in its external active cooling loop.
hydrogen
-
The International Space Station uses ______
for the cooling fluid in its external active cooling loop.
ammonia
-
Thermoelectric cooling employs the _____
effect by using electrical energy for cooling.
seebeck
-
The Mercury spacecraft used _______ for
it high-temperature, high-strength structural material.
titanium
-
The Mercury capsule used a/an _______
type of material for its heat shield
abaltive
-
The highest temperature region near the Mercury capsule was the shock from that reached nearly ______ F during reentry
3,000
-
A higher beta angle (related to orbit inclination angle) will _______ the maximum temperature (and heat loading) of an orbiting spacecraft compared to a lower beta angle.
increase
-
Guidance is generally assumed to be the ______ phase of a booster's or spacecraft's flight
thrust
-
Gravity gradient is a ______ type of attitude stabilization
passive
-
To prevent over-controlling and wasting energy or propellants, the accuracy of the attitude control component of a guidance, navigation & control system (GNC) should be ____ than the
accuracy of the attitude determination component
less
-
The three basic types of attitude and trajectory acceleration sensors are
- Acceleration
- Gyroscopic
- Optical
-
The two types of motion sensors that relate to the two types of motion are ______ and _______.
rotational and translational
-
A ring ____ gyro can measure both types of motion on a spacecraft
laser
-
____ trackers are used to determine the position of a spacecraft in three dimensions.
Star
-
A horizon or limb sensor is used to find the relative position of a spacecraft with respect to a celestial body's _______ or _____.
position or cone
-
Optical terrain guidance was used in the ______-manned spacecraft.
mercury
-
The military's NAVSTAR Global Positioning System (GPS) can be used to determine position and velocity for spacecraft in ___ orbit
LEO
-
Spacecraft attitude and trajectory control can be either _____ or ______, or both
active or passive
-
Solar radiation (photon) pressure can be used for spacecraft and ______ attitude and trajectory control, as was the case for the Mariner 10
passive
-
The two fundamental types of attitude spin stabilization are simple ____ and dual-____.
simple spin and dual-spun
-
Three-axis spacecraft attitude control if furnished by either _______ or by _______ control, or both
thrusters or gyroscopic
-
The most accurate of the three gyroscopic control systems is the _______ _______.
reaction wheels
-
The greatest torque of the three gyroscopic control systems is provided by the _______ ________ gyros
control moment
-
Accumulated error in a spacecraft or aircraft navigation system is also called _____ error.
drift
-
The Apollo spacecraft used a basic _____ guidance system with optical measurements to refine absolute position
GN&C
-
Apollo's optical guidance instruments
included both a telescope and a _____ tracker.
star
-
The heart of the Apollo inertial navigation unit was the _________ _______ Unit (IMU) which was also incorporated in the Space Shuttle's inertial navigation system
intertial measuring
-
The two hand controllers in the Apollo Command Module were the ______ controller and the _______ controller, both of which are found on the Space Shuttle flight deck
-
The Apollo Command and Service Module employed _______ jets to control the attitude of the spacecraft.
reaction
-
A flight director- ______ indicator was used for the 3-dimensional positional and velocity information display for the Apollo astronauts, similar to what is found on the Space Shuttle flight deck.
attitude
-
The two primary attitude and trajectory sensors for the U.S. segment of the International Space Station (ISS) are the _____
gyros and the _____.
-
The U.S. segment employs ____-_______ units for the attitude control element on the ISS
non-propulsive
-
The ISS Russian segment uses both ____-_____ and ______ units for attitude control.
non-propulsive and propulsive
-
The ______ vector carries the attitude, position, and time data used for the ISS GN&C
functions
position
-
The Russian equivalent of the GPS system is
called ________
GLONASS
-
Aerodynamic drag or _______ _______ can be used for slowing spacecraft in orbits around planets with atmospheres, which reduces
the total retrograde thrust needed for orbit insertion
aerodynamic pressure
-
The _____ gradient force is used to desaturate the momentum exchange devices (CMGs, Gyrodynes) on the ISS
gravity
-
Pointing calculations and control operations are needed for the ISS ________, _________ and solar arrays
antennas and radiators
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