Structures and Thermal Lunar Descent Phase Kelly Leffel 2/19/09 Structures and Thermal Lunar Descent Phase Kelly Leffel Structures and Thermal 1

Kelly Leffel Structures and Thermal Updated Mass – Volume Wet Lander Mass 321.2 kilogram(kg) Dry Lander Mass 162.2 kg Dimensions (Height, Top Diameter(d), Base d) 1 meter(m), 1.33 m, 2 m Area for Solar Array 1.39 m^2 Moments of Inertia Izz 107.2 kg-m^2 Iyy = Ixx 70.3 kg-m^2 Ixy = Iyx -53.6 kg-m^2 Izx = Ixz = Izy = Iyz -31.2 kg-m^2 Kelly Leffel Structures and Thermal

Kelly Leffel Structures and Thermal Thermal Control Current (Active/Passive Approach) MLI blanket – 1.5 kg Cryocooler – 8.1 kg and requires 40 W Kelly Leffel Structures and Thermal

Kelly Leffel Structures and Thermal BACK-UP SLIDES Kelly Leffel Structures and Thermal

Kelly Leffel Structures and Thermal Mass – Volume 5 Kelly Leffel Structures and Thermal

Kelly Leffel Structures and Thermal Volume Equations Surface Area(SA) = pi*R*S + pi*R^2 – pi*r*s (NO TOP) Volume(V) = 1/3 * pi * R^2 * H – 1/3 *pi*r^2 Kelly Leffel Structures and Thermal

Moments of Inertia (New height and cm position) Ixx = Iyy = m/4 * (3/2 *r ^2 + 5/24 h^2) = 70.3 kg – m^2 Izz = 3 *m*r^2/4 = 107.2 kg – m^2 Ixy = Iyz = -3*m*r^2/8 = -53.6 kg – m^2 Ixz=Izx=Iyz=Izy = -7/48 * m*r*h = -31.2 kg- m^2 7 Kelly Leffel Structures and Thermal

Kelly Leffel Structures and Thermal Thermal Control MLI Blanket Teflon, Backed outer cover - 0.025 cm thick 0.354 kg Aluminized Kapton Inner Layer (7 Layers) 0.497 kg Dacron Netting separator layer (7 Layers) 0. 287 kg Aluminized Inner Cover 0.323 kg Kelly Leffel Structures and Thermal 8

Kelly Leffel Structures and Thermal Cryocooler NGST MPT 1 stage P-T 1.2 W at 120 K Power Required 40 W Mass 8.1 kg Kelly Leffel Structures and Thermal 9

Kelly Leffel Structures and Thermal References Lander Phase Group for Masses Spacecraft Thermal Control Handbook Volume I and II for Thermal Control data Kelly Leffel Structures and Thermal 10