- Designers are looking at the data handling subsystems for two different spacecraft. One will
orbit Pluto to take high resolution photographs of this dwarf planet and transmit them at a
low data rate to the operations center on Earth. The other will be in low earth orbit to detect
Russian SU-30 afterburners. Discuss the trade-offs in complexity for the CDHS for each of
these spacecraft. - A spacecraft with a requirement for 500 W of continuous power is in an orbit at an altitude
of 1500 km. Compare the performance and mass of Nickel Hydrogen versus Lithium Ion
batteries for this mission. - Research an interplanetary mission and describe its electrical power subsystem. What were
the pros and cons of its approach? - A cube 1 m on a side is in interplanetary space. If the absorptivity, α, is 0.3 and the emissivity,
Ɛ , is 0.7, what is the thermal equilibrium temperature of the cube? Assume an internal heat
of 100W and only one side faces the sun, which has a solar flux = 1367 W/m2
. - An Earth-observation satellite will launch on a vehicle with high-amplitude ascent vibrations
at a frequency of 25 Hz. The mass of the spacecraft is expected to be between 500 and 1000
kg.
a. What range of equivalent spring constants must the structure avoid?
b. Describe an appropriate structure for this mission scenario. - Given a payload mass of 75 kg, estimate the spacecraft’s total mass and volume. 2. Describe the two
major components of an attitude control subsystem – i.e. actuators and sensors, and provide three
examples of each. 3. Describe the three common momentum control devices. What are their main
differences? 4. What are disturbance torques and how do they affect a spacecraft? Calculate orders of
magnitude, rank order them and discuss their relative influence for a: i. LEO satellite ii. GEO satellite 5.
What is momentum dumping? When and why is momentum dumping needed?